Develop Bugs

[INFO] Understanding the risks of having an unlocked bootloader

While unlocking the bootloader on a Galaxy Nexus unleashes the full potential of the bootloader, it also poses a security risk. Even with your lockscreen protected with a pattern/PIN/password, not having flashed a custom recovery, having an anti-theft app installed (maybe even converted/installed as a system app) your phone's data is easily accessible for a knowledgeable thief.
All the thief needs to do is reboot into the bootloader and boot or flash a custom recovery such as ClockWorkMod or TWRP. It's then possible to boot into recovery and use ADB commands to gain access to the phone's data on the internal memory (unless you have it encrypted) and copy/remove files at will.
Granted, the risk seems low. The thief would not only require knowledge of fastboot, he would have to turn off the phone before you have issued a wipe command using an anti-theft app. You could of course flash back the stock recovery & relock the bootloader after being done with flashing stuff, but that would require you to unlock it again if needed which will erase your userdata.
There are two ways to tackle this security risk AND retain unlocked bootloader functionality without losing userdata.
1) Encrypt your phone using Android's built-in encryption feature
Advantages:
- you can leave your bootloader unlocked & leave a custom recovery installed without risk of exposing your data.
Disadvantages:
- unless the custom recovery can decrypt your phone, you cannot use all of its features.
- when decryption fails, you cannot access your phone and need to do a factory reset from recovery. Users have reported not being able to decrypt after applying OTA updates.
- the encryption process is irreversible. The only way to return to an unencrypted phone is to perform a factory data reset which erases all your data.
2) Unlock & relock the bootloader from Android OS
Prerequisites:
- root access
- an app that can unlock/relock the bootloader at will such as BootUnlocker
Steps
Root your device using one of the many guides out there (recommended guide). Install BootUnlocker. Reflash stock recovery and lock the bootloader. Whenever you need an unlocked bootloader again, simply use Bootlocker to unlock it (this won't wipe userdata). When done, relock.
Advantages:
- doesn't require encryption (for those who do not wish to use it).
Disadvantages:
- relies on third-party apps.
- method will not work if you lose root access for whatever reason.
- method will not work when you cannot boot into Android for whatever reason.
USB debugging
Strictly not related to the bootloader, but for maximum security disable USB debugging when not required. Having it enabled allows the execution of ADB commands even if the lockscreen is still locked. Myself, I use Tasker in combination with Secure Settings to automatically enable USB debugging when my device is connected to my home WiFi access point but disabled if not connected.
The following video demonstrates what a knowledgeable thief can do with your phone when you have USB debugging enabled by default: http://www.youtube.com/watch?v=ah7DWawLax8&t=7m0s
More info: recently, an exploit has been discovered that will enable gaining root without going through the 'traditional' process of unlocking the bootloader & flashing a custom recovery in order to flash Superuser or SuperSU packages. See this post for a guide.
Play store devices
Devices bought directly from Google's Play Store apparently do NOT wipe userdata after fastboot oem unlock. So for these devices, method number 2 does not add any security. For more info, read this thread: http://forum.xda-developers.com/showthread.php?t=1650830

Very well written!!
One thing you may want to tie in to your explanation is the effect of having USB Debugging enabled - it's easy to gain root (and subsequently unlock your bootloader) with it enabled, even with a locked bootloader.
Sent from my Galaxy Nexus using Tapatalk 2

Added some information regarding USB debugging. Thanks for the tip efrant.

Good read:good:

Do you have to be on stock rom to lock the bootloader ?

Oscuras said:
Do you have to be on stock rom to lock the bootloader ?
Click to expand...
Click to collapse
Nope.
Sent from my Galaxy Nexus using Tapatalk 2

Thanks for this :good:
Trying to wrap my head around this with regards to anti theft protection etc.
Currently have an unlocked bootloader, custom rom, and root. If I have something like Cerberus or Avast running (both claim to work as system apps so will not be deleted via hard reset), have debugging unchecked and a pin lock at screen on - if I lock bootloader now, how secure am I to data theft?
Presumably, with debug disabled, fastboot from pc command prompt to unlock bootloader will not work? Can ODIN be used to flash a new ROM and if so my system apps (and thus the security apps) will be wiped, rendering the whole thing useless?
Thanks

Guiding.God said:
Thanks for this :good:
Trying to wrap my head around this with regards to anti theft protection etc.
Currently have an unlocked bootloader, custom rom, and root. If I have something like Cerberus or Avast running (both claim to work as system apps so will not be deleted via hard reset), have debugging unchecked and a pin lock at screen on - if I lock bootloader now, how secure am I to data theft?
Presumably, with debug disabled, fastboot from pc command prompt to unlock bootloader will not work? Can ODIN be used to flash a new ROM and if so my system apps (and thus the security apps) will be wiped, rendering the whole thing useless?
Thanks
Click to expand...
Click to collapse
If you have the stock recovery (custom will allow adb), your personal data is as secure as it can be. Of course, you cannot stop anybody from booting into your bootloader and run fastboot oem unlock OR use Odin to flash your device. However, doing so will effectively wipe your device so your personal data cannot be accessed.

I would more worry about my phone then data because I have nothing important on it...
Sent from my Galaxy Nexus using xda premium

Petrovski80 said:
If you have the stock recovery (custom will allow adb), your personal data is as secure as it can be. Of course, you cannot stop anybody from booting into your bootloader and run fastboot oem unlock OR use Odin to flash your device. However, doing so will effectively wipe your device so your personal data cannot be accessed.
Click to expand...
Click to collapse
qtwrk said:
I would more worry about my phone then data because I have nothing important on it...
Sent from my Galaxy Nexus using xda premium
Click to expand...
Click to collapse
Thanks for the clarification.
And I worry more about the work related data, the phone itself is insured

This is important info, and a lot of folks probably don't realize how open they are. This should be stickied or better yet included in the stickied thread where the bootloader unlock instructions are. Thanks for the post.

Great info. One question, I use Titanium Backup automated nightly to backup data and new apps, and it requires USB Debugging on.
I suppose I could use Secure Settings to turn USB Debugging on and off, but that means an opening is available once a day for a few minutes. Thoughts?

Pkt_Lnt said:
Great info. One question, I use Titanium Backup automated nightly to backup data and new apps, and it requires USB Debugging on.
I suppose I could use Secure Settings to turn USB Debugging on and off, but that means an opening is available once a day for a few minutes. Thoughts?
Click to expand...
Click to collapse
You could do as I do: use secure settings in combination with tasker so USB debugging will only be enabled when connected to your home Wifi. It will allow your nightly TiB backups, and I assume the 'ADB opening' is not an issue when at home (not many thieves there I hope).

Petrovski80 said:
You could do as I do: use secure settings in combination with tasker so USB debugging will only be enabled when connected to your home Wifi. It will allow your nightly TiB backups, and I assume the 'ADB opening' is not an issue when at home (not many thieves there I hope).
Click to expand...
Click to collapse
I downloaded Secure Settings to check it, and it will work. I have AutomateIT Pro and it does not support plug-ins. I have been finding more tasks that it seems only Tasker can perform, I guess it is time to get it. Thank you.

Petrovski80 said:
You could do as I do: use secure settings in combination with tasker so USB debugging will only be enabled when connected to your home Wifi. It will allow your nightly TiB backups, and I assume the 'ADB opening' is not an issue when at home (not many thieves there I hope).
Click to expand...
Click to collapse
Great idea.

Petrovski80 said:
You could do as I do: use secure settings in combination with tasker so USB debugging will only be enabled when connected to your home Wifi. It will allow your nightly TiB backups, and I assume the 'ADB opening' is not an issue when at home (not many thieves there I hope).
Click to expand...
Click to collapse
A Jasager router could exploit this if you have WiFi enabled in public. When WiFi is enabled and not connected to a network, every 'x' period of time (depending upon your wifi.supplicant_scan_interval setting in your build.prop) your phone will send out a packet saying "hey, is xyz network around?". It will do that for every network that you have saved settings for.
Under normal circumstances, you get no reply when away from your home router and the phone just waits the interval to try again. A Jasager ("yes man" in German) router waits for a device to send out those packets and simply responds "yep, that's me!". Under this circumstance, your phone would authenticate to their router and think it's on your home network, triggering any applicable Tasker options.
This is one of the reasons that I do not have WiFi enabled unless I actively want to be connected to a router in the area.
Also, I have USB Debugging disabled and my TiBu backups run perfectly fine according to schedule.

I am not a paranoid worry wart so the risk are more than worth it for me. There's nothing on here that I would care if some one got a hold of anyway.
Sent from my Galaxy Nexus using xda premium

Cilraaz said:
A Jasager router could exploit this if you have WiFi enabled in public. When WiFi is enabled and not connected to a network, every 'x' period of time (depending upon your wifi.supplicant_scan_interval setting in your build.prop) your phone will send out a packet saying "hey, is xyz network around?". It will do that for every network that you have saved settings for.
Under normal circumstances, you get no reply when away from your home router and the phone just waits the interval to try again. A Jasager ("yes man" in German) router waits for a device to send out those packets and simply responds "yep, that's me!". Under this circumstance, your phone would authenticate to their router and think it's on your home network, triggering any applicable Tasker options.
This is one of the reasons that I do not have WiFi enabled unless I actively want to be connected to a router in the area.
Also, I have USB Debugging disabled and my TiBu backups run perfectly fine according to schedule.
Click to expand...
Click to collapse
Maybe. Tasker checks both the SSID and the MAC address of my router before it returns 'wifi connected' as true and enables USB debugging. Sure, MAC addresses are easy to spoof, but I don't think the MAC address is part of the broadcast packet (I haven't checked) because that's simply a value stored by Tasker itself.
And even if it is, the combination of a lost/stolen GNEX and a thief who modded their router with jasager firmware + knows ADB is too unlikely for me to worry about it. But indeed, for maximum security it's best not to automate enabling of USB debugging.

Petrovski80 said:
Maybe. Tasker checks both the SSID and the MAC address of my router before it returns 'wifi connected' as true and enables USB debugging. Sure, MAC addresses are easy to spoof, but I don't think the MAC address is part of the broadcast packet (I haven't checked) because that's simply a value stored by Tasker itself.
And even if it is, the combination of a lost/stolen GNEX and a thief who modded their router with jasager firmware + knows ADB is too unlikely for me to worry about it. But indeed, for maximum security it's best not to automate enabling of USB debugging.
Click to expand...
Click to collapse
The MAC check would almost certainly keep you safe.
It's interesting stumbling across this thread after having just seen a podcast episode about Android hacking. If anyone is interested, check out Hak5. One of their recent episodes is about Android hacking via ADB, specifically something called P2PADB that was created for quick device-to-device ADB access. It was fairly amazing the things this person could do to a phone that has USB Debugging enabled.

Cilraaz said:
The MAC check would almost certainly keep you safe.
It's interesting stumbling across this thread after having just seen a podcast episode about Android hacking. If anyone is interested, check out Hak5. One of their recent episodes is about Android hacking via ADB, specifically something called P2PADB that was created for quick device-to-device ADB access. It was fairly amazing the things this person could do to a phone that has USB Debugging enabled.
Click to expand...
Click to collapse
Watching the video right now. Personally, I find it a gaping security hole that the ADB interface is accessible through a locked lockscreen.
For anyone interested in the vid: the ADB part starts at 7:00.
Edit: amazing video. It really proves what a knowledgeable thief can do when you have USB debugging enabled, especially when combined with root access (don't we all?). I'm going to add the video to my post. Thanks for the info Cilraaz!

[Q] CM Version 11-20140113, ADB, Developer options missing. New ROM or where?

With the recent availability of the Android Wear SDK, I thought I should try developing for it, and Android in general. Got some app ideas to try out. So, in short my current ROM does not have the Settings > Developer Options option to get to Enable USB Debuggingso I can connect to my phone via ADB over USB.
My question is two fold.
Assuming I am not blind, and Developer Options really is missing, what am I messing up?
or
Which 4.4.2 build gives me the option for USB debugging and the other developer settings?

galorin said:
With the recent availability of the Android Wear SDK, I thought I should try developing for it, and Android in general. Got some app ideas to try out. So, in short my current ROM does not have the Settings > Developer Options option to get to Enable USB Debuggingso I can connect to my phone via ADB over USB.
My question is two fold.
Assuming I am not blind, and Developer Options really is missing, what am I messing up?
or
Which 4.4.2 build gives me the option for USB debugging and the other developer settings?
Click to expand...
Click to collapse
Go to the settings..About phone...Build number...Tap it 7 times

Thanks for that! I did not know that was what I was supposed to do. All sorted now.

[Q] Cant access developer options.

Hi,
I have a very strange issue and I am hoping that someone has a solution to this problem.
The tablet SM-T705 came with Build number KOT49H.T705XXU1ANG2 out of the box and it is not upgradeable.
Recently I bought a samsung galaxy tab s t705, The first thing that I wanted to do is root my new toy.
Obviously the first step in the process is to enable USB Debugging but it is a no go !
Here is what I am doing:
Settings > General > About device , Then tap the Build number 7 times.
Once I got the message that the developer mode is now enabled, I go back to the General tab but the "Developer options" are nowhere to be found.
I installed Nova launcher and tried to crate a shortcut for for the "Developer options" but all it does is throw me to the General settings tab in the settings.
I tried to factory reset the device and repeat the process but not luck.
I even tried some apps that are just shortcuts for the Developer options but it didn't help.
Any suggestions ?
I really need root (cant stand all the bloatware).
Thank you for your help !
/
16k

16k said:
Hi,
I have a very strange issue and I am hoping that someone has a solution to this problem.
The tablet SM-T705 came with Build number KOT49H.T705XXU1ANG2 out of the box and it is not upgradeable.
Recently I bought a samsung galaxy tab s t705, The first thing that I wanted to do is root my new toy.
Obviously the first step in the process is to enable USB Debugging but it is a no go !
Here is what I am doing:
Settings > General > About device , Then tap the Build number 7 times.
Once I got the message that the developer mode is now enabled, I go back to the General tab but the "Developer options" are nowhere to be found.
I installed Nova launcher and tried to crate a shortcut for for the "Developer options" but all it does is throw me to the General settings tab in the settings.
I tried to factory reset the device and repeat the process but not luck.
I even tried some apps that are just shortcuts for the Developer options but it didn't help.
Any suggestions ?
I really need root (cant stand all the bloatware).
Thank you for your help !
/
16k
Click to expand...
Click to collapse
Your on an old firmware, so that means you'll need to upgrade. Download mode does not need usb debugging. Simply put your device in download mode, flash newer firmware with odin, then root with cfautoroot. USB debugging is only needed to connect to PC while device is on. Hope this helps!

Thank!
DUHAsianSKILLZ said:
Your on an old firmware, so that means you'll need to upgrade. Download mode does not need usb debugging. Simply put your device in download mode, flash newer firmware with odin, then root with cfautoroot. USB debugging is only needed to connect to PC while device is on. Hope this helps!
Click to expand...
Click to collapse
This is the latest version based on Samsung's website and I really need to get usb debug going (not only for root).
Thanks for the help.

Which region is the device?

[Q] USB Debugging mode blocked by Server?

Alright, heres a new one boys. I recently updated my US Cellular G3 to 5.0, and wanted to root. The first and only problem I have is when I go to allow debugging, the tab is grey out and underneath it says, "USB Debugging is disabled by server policy"
What can I do to change this? Any advice would be appreciated.
Thanks!

I have same problem when the G3 ìs plug on the pc , is it the case for you here ? If yes unplug your G3 and then you can activate debugging

jac10000 said:
I have same problem when the G3 ìs plug on the pc , is it the case for you here ? If yes unplug your G3 and then you can activate debugging
Click to expand...
Click to collapse
It does not show up ever, unplugged or plugged in.

Jacobsen Chief said:
It does not show up ever, unplugged or plugged in.
Click to expand...
Click to collapse
Ok try this :
Solution 1 : Have you switche the activate button ?
{
"lightbox_close": "Close",
"lightbox_next": "Next",
"lightbox_previous": "Previous",
"lightbox_error": "The requested content cannot be loaded. Please try again later.",
"lightbox_start_slideshow": "Start slideshow",
"lightbox_stop_slideshow": "Stop slideshow",
"lightbox_full_screen": "Full screen",
"lightbox_thumbnails": "Thumbnails",
"lightbox_download": "Download",
"lightbox_share": "Share",
"lightbox_zoom": "Zoom",
"lightbox_new_window": "New window",
"lightbox_toggle_sidebar": "Toggle sidebar"
}
Solution 2 : go to menu and select default parameters and try another
Solution 3 : Test the differents options (PTP, MTP, ONLY CHARGE) and each time try to activate Debugging mode when you plug to pc
Solution 4 : Go to this menu and select program install then try to activate debugging mode
Solution 5 : Revoke the authorizations and try to activate the debugging mode

jac10000 said:
Ok try this :
Solution 1 : Have you switche the activate button ?
Solution 2 : go to menu and select default parameters and try another
Solution 3 : Test the differents options (PTP, MTP, ONLY CHARGE) and each time try to activate Debugging mode when you plug to pc
Solution 4 : Go to this menu and select program install then try to activate debugging mode
Solution 5 : Revoke the authorizations and try to activate the debugging mode
Click to expand...
Click to collapse
None of those things worked... Ive never seen this before. Here is a screenshot

I think it's a bug with lollipop and it seem that the solution is the factory reset

jac10000 said:
I think it's a bug with lollipop and it seem that the solution is the factory reset
Click to expand...
Click to collapse
Just did a factory reset-Same result. I could understand them blocking this to protect against root (I wonder why LG and US Cellular are so against it), but what if I was actually a developer wanting to use SDK or make an app? It kind of ruins that feature. Any other suggestions?

And by flashing kdz firmware ? Il seems thant the update by OTA to 5 which is the cause of your problem.
Can be that by installing KDZ firmware you have this function ...
When you are on KitKat can you activate debugging ?
Type here your imei to have the lastest version of kdz : http://www.lg-phone-firmware.com/index.php?firmware=1

jac10000 said:
And by flashing kdz firmware ? Il seems thant the update by OTA to 5 which is the cause of your problem.
Can be that by installing KDZ firmware you have this function ...
When you are on KitKat can you activate debugging ?
Type here your imei to have the lastest version of kdz : http://www.lg-phone-firmware.com/index.php?firmware=1
Click to expand...
Click to collapse
I tried installing the KDZ though TWRP, but when it failed I decided to go ahead and just update it with the LG Software. I had read other articles on rooting the G3 with Lollipop, so I didn't really worry about re-rooting it until I ran into this problem.
For installing with the KDZ, I extracted Modem, Boot, and System.imgs, but the System.img failed. And yes with KitKat, I could use debugging.

facing the same problem myself, did you ever find a solution? because this is getting really frustrating

Dragontype191 said:
facing the same problem myself, did you ever find a solution? because this is getting really frustrating
Click to expand...
Click to collapse
Update, I made a post over on the US Cellular forums and if anyone is having this problem it is the McAfee bundled in with the new lollipop update, just find the McAfee app (you can't uninstall it without root) clear the cache on it and click the manage space button and it'll ask you to put in your pin to deactivate it, after I did that my debugging is back!

Dragontype191 said:
If anyone is having this problem it is the McAfee bundled in with the new lollipop update, just find the McAfee app (you can't uninstall it without root) clear the cache on it and click the manage space button and it'll ask you to put in your pin to deactivate it, after I did that my debugging is back!
Click to expand...
Click to collapse
Wanted to say thanks for posting this information in the General Area.
For those folk who are not as technically proficient I have laid out your instructions.
__________________________
If anyone is having this problem it is due to the McAfee Security App bundled in with the Lollipop update, you can't uninstall it without root but if you clear the cache on it and manage the space you will get debugging back.
Go to "Setting"
Go to "Apps"
Select the "All" Tab
Select the "McAfee Security" App
Click the "Clear cache" button
Click the "Manage space" button
Enter your PIN
Click "OK"
Your debugging option will now be available.

To Enable USB Debugging mode that is blocked by Server you have to dissable McAfee Mobile SECURITY

Jacobsen Chief said:
Just did a factory reset-Same result. I could understand them blocking this to protect against root (I wonder why LG and US Cellular are so against it), but what if I was actually a developer wanting to use SDK or make an app? It kind of ruins that feature. Any other suggestions?
Click to expand...
Click to collapse
Click on revoke USB debugging authorization. Click ok. Turn off developers option on the verg top. Turn it on again and voila you now have an option to put a check on usb debugging. Hope it works for you...
LG G3 Android 5.0 user

Jacobsen Chief said:
Alright, heres a new one boys. I recently updated my US Cellular G3 to 5.0, and wanted to root. The first and only problem I have is when I go to allow debugging, the tab is grey out and underneath it says, "USB Debugging is disabled by server policy"
What can I do to change this? Any advice would be appreciated.
Thanks!
Click to expand...
Click to collapse
PLEASE PLEASE PLEASE READ! This is probably the fix to this problem all because of a stupid built in app that the g3 includes now and it has to do with McAfee Security.
If it worked mark this up for those future people who have issues!!
Okay so i found out what the problem was. I used to own and lg g2 but recently got the g3. Im with sprint fyi...but anyways i was tinkering around with it being 17 and stupid i bricked the phone, so i eventually got it fixed again. Previously my phone was rooted but now it wasnt so then i went back to get developer options activated and usb debugging active as well, however i ran into this problem. This stumped me because i had it rooted before. So then i was thinking what did i give accsess to that i hadnt before that isnt allowing usb debbugging...well it had to be an app since this didnt happen to me before and it had to be an app that i hadnt used before i bricked my phone and then i thought it has to be a built in app since no third party app would have that permission to say something like "disabled by server policy" then i realised okay what does the g3 have that the g2 doesnt have and is built in.....Mcafee security and Lookout! And it made sence because when you check the box for usb debugging you are making your android less secure! So i entered the McAfee app tapped settings ---> and the first option should be "lock down device" TURN THAT OFF! That right there is your culprit now go back to dev options and you can now enable usb debugging again please rate this up so people can see what was going on and how to fix it. No need to reset your phone. Also let me know if this worked. I have got nothing but positive feed back so far.

I am having the same problem and i have an LG Lucky and usb debugging is disabled by server policy and i really dont know what to do but it worked at first then later it got blocked.

help please
PokrTom said:
Wanted to say thanks for posting this information in the General Area.
For those folk who are not as technically proficient I have laid out your instructions.
__________________________
If anyone is having this problem it is due to the McAfee Security App bundled in with the Lollipop update, you can't uninstall it without root but if you clear the cache on it and manage the space you will get debugging back.
Go to "Setting"
Go to "Apps"
Select the "All" Tab
Select the "McAfee Security" App
Click the "Clear cache" button
Click the "Manage space" button
Enter your PIN
Click "OK"
Your debugging option will now be available.
Click to expand...
Click to collapse
My debugging option is not available. Do I need to have my old sim card in place? It was from at&t. I took it out a while back. Is that why I cannot chose the Debug option? Ive tried everything on this forum.

I had the same issue. It was blocked by mcafee. I had to change it from " locked down mode" to unlocked mode, then turn developer options off and right baxk on. Then i was allowed to turn on usb debugging

Solution
Okay, so I was having the same issue. I contacted LG, Google, and finally AT&T after I tried a lot of the suggested solutions on this post. The AT&T tech support rep helped me research this issue. The issue is that an app on your phone is not allowing you to be able to debug, most likely a security app. I suppose that it thinks by allowing your phone to debug could cause harm to the device. The app that was keeping me from debugging was McAfee, which came pre-installed. When you disable this app, or whichever app is keeping you from debugging, you will then notice that the message 'USB debugging is disabled by server policy' goes away. I hope this helps you all, and happy developing!
God is good!!!

sir can you all help me for this problem? i can't update and fix my g3! ugrrrr !!!1

USB debugging mode issue with several apps

Sorry for my English.
There are a few apps where you are not allowed to use USB debugging mode while working with them (Fate/Grand Order, Fortnite, some banking apps, etc).
Two days ago I've run into a problem with Fate/Grand Order. I turned on the debug mode and after that turned it off. However, the app still throws an error about USB debugging. The support team said that I should contact my manufacturer. I've found a theme on Xiaomi forum (can't post a link because of anti-spam) about this problem. Some users with POCO F1 have this problem too.
The only solution is factory reset.
Does anyone have the same problem?

ArianEpsilon said:
Sorry for my English.
There are a few apps where you are not allowed to use USB debugging mode while working with them (Fate/Grand Order, Fortnite, some banking apps, etc).
Two days ago I've run into a problem with Fate/Grand Order. I turned on the debug mode and after that turned it off. However, the app still throws an error about USB debugging. The support team said that I should contact my manufacturer. I've found a theme on Xiaomi forum (can't post a link because of anti-spam) about this problem. Some users with POCO F1 have this problem too.
The only solution is factory reset.
Does anyone have the same problem?
Click to expand...
Click to collapse
clear apps data and reboot ?? plug cable in to pc and toggle the settings??

boe323 said:
clear apps data and reboot ?? plug cable in to pc and toggle the settings??
Click to expand...
Click to collapse
I've tried this but nothing helped. I flashed 10.0.3.0 ROM and now everything works perfectly even after enabling/disabling USB debugging mode.
My friend also has Mi A2 Lite so I asked him to check this bug. He installed the game (he was using ROM 10.0.3.0) and after turning on and off debug mode everything worked fine. Then I asked him to install new 10.0.4.0 firmware and check this bug again. He got USB debug error even after disabling USB debugging.
So new February patch makes unable to play some games (such as Fate/Grand Order, Fortnite and so on) where it's not allowed to use USB debugging.

ArianEpsilon said:
Sorry for my English.
There are a few apps where you are not allowed to use USB debugging mode while working with them (Fate/Grand Order, Fortnite, some banking apps, etc).
Two days ago I've run into a problem with Fate/Grand Order. I turned on the debug mode and after that turned it off. However, the app still throws an error about USB debugging. The support team said that I should contact my manufacturer. I've found a theme on Xiaomi forum (can't post a link because of anti-spam) about this problem. Some users with POCO F1 have this problem too.
The only solution is factory reset.
Does anyone have the same problem?
Click to expand...
Click to collapse
You need to disable developer options for fortnite to work!I'm pretty sure that the other apps also require you to disable developer options

gz26 said:
You need to disable developer options for fortnite to work!I'm pretty sure that the other apps also require you to disable developer options
Click to expand...
Click to collapse
I know, as I said earlier, it doesn't work. If you try to enable and disable USB debug for the first time on 10.0.4.0 you will get an error about USB debug.
On 10.0.3.0 everything works fine. Seems USB debugging in 10.0.4.0 firmware is kinda broken. All applications detect it as turned on.

ArianEpsilon said:
Sorry for my English.
There are a few apps where you are not allowed to use USB debugging mode while working with them (Fate/Grand Order, Fortnite, some banking apps, etc).
Two days ago I've run into a problem with Fate/Grand Order. I turned on the debug mode and after that turned it off. However, the app still throws an error about USB debugging. The support team said that I should contact my manufacturer. I've found a theme on Xiaomi forum (can't post a link because of anti-spam) about this problem. Some users with POCO F1 have this problem too.
The only solution is factory reset.
Does anyone have the same problem?
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You can unable it in Dev options.
Btw you can't run Fortnite on Mi A2 Lite, check sys requirements for the game.

wynix black said:
You can unable it in Dev options.
Btw you can't run Fortnite on Mi A2 Lite, check sys requirements for the game.
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If I disable it nothing will change. There is a bug in 10.0.4.0 firmware. USB debugging doesn't turn off completely. I'm sorry, but did you even read my message?

Ok, I know 3 people who have the same problem. Does anyone here have the same problem with 10.0.4.0?