Develop Bugs

[Q] Help connecting with QPST

Hi All,
I can't seem to get QPST to work with my Epic 4g (trying to change the PRL). I've followed this guide: http://forum.xda-developers.com/showthread.php?t=898628
The issue is (as far as I can tell), the computer isn't using the correct drivers. I can't get the phone to show up as a com port regardless of what UART/USB settings I try, charging/USB tethering, or USB debugging enabled/disabled.
I've attached two pics from device manager, the first is using USB tethering, the other putting it in Charging mode. I've even tried reinstalling the Samsung USB drivers and manually updating them with the phone connected -- but no luck (it says the best drivers are already installed).
Any suggestions?

Found the fix: need to plug in the phone with PDA/USB selected and switch to MODEM/USB after. Otherwise my computer doesn't even detect a USB connection.

[Q] after installing android SDK and rooting Nexus File transfer stops working

I've never had a problem with android file transfer up till I rooted today. My wife has a stock Nexus 7 and I can plug her Nexus into my computer and the file transfer app will start. I have usb debugging turned on and the usb connection on my tablet is set to Media device.
Now as I'm typing this my Nexus has been connect to my mac for about an hour. I just went to the USB settings to make sure I had Media device selected and the file transfer window popped up out of nowhere. I killed it and tried again and it won't come up. Maybe in an hour or so if it does the same thing.
Any ideas as to what's going on? Very strange behavior.

Disable USB debugging.
Unplug/plug in your nexus.
The USB IDs change for some reason when you have USB debugging turned on and the MTP device isn't recognized as such. PTP (camera) mode continues to work for both cases though.

Thanks for the suggestion but It still fails. I disabled debugging and still can't connect. Switching USB modes didn't help either.

If that doesn't work uninstall the adb driver & then plug your tablet back in so it will reinstall

My next suggestion would to reboot the tablet with USB debugging turned off.
If that doesn't work, my next suggestion would be to delete the existing drivers and force reinstall.
All with USB debugging turned off.

johnnyninja said:
I've never had a problem with android file transfer up till I rooted today. My wife has a stock Nexus 7 and I can plug her Nexus into my computer and the file transfer app will start. I have usb debugging turned on and the usb connection on my tablet is set to Media device.
Now as I'm typing this my Nexus has been connect to my mac for about an hour. I just went to the USB settings to make sure I had Media device selected and the file transfer window popped up out of nowhere. I killed it and tried again and it won't come up. Maybe in an hour or so if it does the same thing.
Any ideas as to what's going on? Very strange behavior.
Click to expand...
Click to collapse
Make sure after you plug in your device you're looking at your tab and click OK on the pop up........
Sent from my Nexus 7

Thanks for all the suggestions. It's working now. I was just about ready to delete the driver and the tablet started to be recognized consistently. I was in the settings screen and toggled debugging on and off while plugging in the tablet. I noticed the info bar at the top alternating between showing "debugging" and "media device" and I selected each one a couple of times when they came up. I think that it finally worked through the ID confusion that was mentions. I'll follow the the rest of the instructions if the problem comes back.
Thanks again.

It's acting up again so I'm going to try deleting the drivers. I thought I knew what to do but I can't find any information. What's the procedure to delete the driver? I'm running os x lion

I've tried every suggestion in all of these threads so far & nothing worked. Even after I deleted the ADB drivers, windows 7 would automatically reinstall them. When I tried to update the drivers, win7 said they already had the best drivers (ADB).
Here's what worked for me:
I had to turn off USB debugging, delete the ADB drivers in Device Manager, then reboot the device while it's still plugged in. Windows recognized the device as an MTP device & installed the drivers before it even fully booted.

I'm not sure how I finally resolved the problem on my mac. I toggled debugging on and off and rebooted a couple of times. That may have done it. I also ran the adb script in the SDK platform-tools folder. I don't know what that script does exactly but possibly it reinitialized the driver and ID.
Anyway, hopefully these workflows will work for others.

johnnyninja said:
I'm not sure how I finally resolved the problem on my mac. I toggled debugging on and off and rebooted a couple of times. That may have done it. I also ran the adb script in the SDK platform-tools folder. I don't know what that script does exactly but possibly it reinitialized the driver and ID.
Anyway, hopefully these workflows will work for others.
Click to expand...
Click to collapse
Rooted my nexus 7 (2012) last night and struggling with my laptop not recognizing it. This thread solved it!
Delete the ADB on my window, toggle off debugging and restart the nexus 7 with usb connected to laptop. works like a charm.
Thank you!

Guys, my N4 got this problem too.. until just a few minute ago
I read somewhere ini goge groups (i think N5 group), and found explanation that we can change ADB or MTP "mode" on device manager. On "Androoid ADB Device" right click and select "Update Driver Software". Click "Browse My Computer for Driver Software" and then "Let me pick from blablabla...." And then select MTP USB Device, "next" and my N4 detected on Windows Explorer.
Hope it will be usefull for you guys.

[Q] My computer cannot recognize my devices MTP

I just got my Nexus 7(2013) device.
I used to transfer files between my computer and my Nexus 4.
When I plugged in my N4, my computer recognizes my N4 and device manager showed there is a portable devices "Nexus 4"
However when I plugged in my new N7, my computer cannot detect it and device manager showed "Android Device" with "Android Composite ADB Interface" under it.
I cannot find any new drive in My Computer although the device is charging through USB.
I have tried to disable/enable USB Debugging, using different USB cables, switching USB option between MTP and PTP and reinstalling Nexus usb driver from google and all of them do not work.
May I ask for any solution?
Thanks:fingers-crossed::fingers-crossed:

Uninstall/remove the drivers
reboot
then reinstall using these drivers
http://dl-ssl.google.com//android/repository/latest_usb_driver_windows.zip
Even if you did it before, try again, with the removal of drivers and the reboot.
Also you may want to try different ports, cables, computers

sfhub said:
Uninstall/remove the drivers
reboot
then reinstall using these drivers
http://dl-ssl.google.com//android/repository/latest_usb_driver_windows.zip
Even if you did it before, try again, with the removal of drivers and the reboot.
Also you may want to try different ports, cables, computers
Click to expand...
Click to collapse
I've tried that before
I may now try a few times more
By the way, I realized that I can use Wugfresh toolkit and completed the full driver test to bootloader mode. However, I cant even detect the hard drive.

I finally enabled to use PTP to access the photos.
However I am still unable to use MTP to transfer other types of files..
Any help?:fingers-crossed::fingers-crossed:

EggShaarawy said:
I finally enabled to use PTP to access the photos.
However I am still unable to use MTP to transfer other types of files..
Any help?:fingers-crossed::fingers-crossed:
Click to expand...
Click to collapse
Please perform the following even if you have done it before.
In this current state, turn on MTP. Then turn off USB debugging. See if MTP shows up. If so, use this fix to get MTP working with USB debugging.
[FIX] MTP with USB debugging / ADB within Recovery (windows/nexus7)

sfhub said:
Please perform the following even if you have done it before.
In this current state, turn on MTP. Then turn off USB debugging. See if MTP shows up. If so, use this fix to get MTP working with USB debugging.
[FIX] MTP with USB debugging / ADB within Recovery (windows/nexus7)
Click to expand...
Click to collapse
I am sorry that I cannot understand it completely.
May I ask
1. Should I uninstall just the entry with Nexus 7 as description in Nirsoft USBDeview and then reboot?
2. You mentioned that "When you turn on USB debugging and windows asks for an MTP driver, just provide mtp_driver.zip". How can I use the zip file? After rebooting and enabling USB debugging, my toolbar on bottom-right has a icon showing I have a MTP and I can choose to "remove MTP safely" just like plugging in a USB flash drive. However, there is not a hard drive in My Computer. Maybe is it the difference between Windows XP and WIndows 7? Or did I misunderstand your instruction?
Thanks for helping! :good:

I finally did it with USB debugging and MTP on.
I occasionally update the Android ADB Interface driver and install Composite USB Device from the list and my computer detects my hard drive!!
Is it possible to get my MTP working without enabling USB Debugging or is it normal to detect mtp with USB Debugging on? :good:

EggShaarawy said:
I finally did it with USB debugging and MTP on.
Click to expand...
Click to collapse
One of the drivers you installed previously which was modified to get MTP working. was implemented too aggressively and is now blocking your ability to use MTP with USB debugging turned off.
For normal systems with no drivers loaded, they have the opposite problem, in that they can get MTP working when USB debugging is disabled, but lose MTP when USB debugging is enabled.
When USB debugging is disabled and MTP is enabled, the USB port advertises that it is compatible with standard MTP drivers, so windows automatically installs. However if you have a custom driver installed, it can block that automatic process.
With USB debugging turned on, the USB port no longer advertises MTP compatibility, so windows is normally confused and doesn't know what driver to use. That you were able to get it working with USB debugging enabled proves to me that you have a custom driver installed that was modified to get MTP working.
The way I wrote my changes to the MTP driver was to leave the standard MTP alone and only intercept the MTP when USB debugging is enabled. Thus my changes don't block normal MTP operation when USB debugging is disabled.
EggShaarawy said:
Is it possible to get my MTP working without enabling USB Debugging or is it normal to detect mtp with USB Debugging on? :good:
Click to expand...
Click to collapse
Yes, but you are going to need to figure out which driver you installed is causing the issue and remove it so it doesn't get in the way.
Alternatively, try a different PC that has never had drivers installed and use just the one I pointed you at earlier.
You don't use the zip file directly, you unzip the contents and will have a .inf file.
When windows asks for a driver (USB debugging turned on and MTP turned on) you point the install at the .inf provided. It will do the rest automatically.

sfhub said:
One of the drivers you installed previously which was modified to get MTP working. was implemented too aggressively and is now blocking your ability to use MTP with USB debugging turned off.
For normal systems with no drivers loaded, they have the opposite problem, in that they can get MTP working when USB debugging is disabled, but lose MTP when USB debugging is enabled.
When USB debugging is disabled and MTP is enabled, the USB port advertises that it is compatible with standard MTP drivers, so windows automatically installs. However if you have a custom driver installed, it can block that automatic process.
With USB debugging turned on, the USB port no longer advertises MTP compatibility, so windows is normally confused and doesn't know what driver to use. That you were able to get it working with USB debugging enabled proves to me that you have a custom driver installed that was modified to get MTP working.
The way I wrote my changes to the MTP driver was to leave the standard MTP alone and only intercept the MTP when USB debugging is enabled. Thus my changes don't block normal MTP operation when USB debugging is disabled.
Yes, but you are going to need to figure out which driver you installed is causing the issue and remove it so it doesn't get in the way.
Alternatively, try a different PC that has never had drivers installed and use just the one I pointed you at earlier.
You don't use the zip file directly, you unzip the contents and will have a .inf file.
When windows asks for a driver (USB debugging turned on and MTP turned on) you point the install at the .inf provided. It will do the rest automatically.
Click to expand...
Click to collapse
I have been using the same computer to root Galaxy Nexus and Nexus 4 and I remembered I have been using some tool similar to the one you provided.
Maybe it makes my computer cannot recognize the MTP
Anyway, Thanks

[Q] MTP Connection

Ok so I'm extraordinarily frustrated with getting this to work. I've searched the forum to the point of a headache. Something about the .inf file and hardwar id's. I've uninstalled and reinstalled the drivers a million times. I've even reflashed the stock rom. Can anyone help? usb debugging works and PTP works. Currently back to stock and all drivers currently uninstalled.

mta1981 said:
Ok so I'm extraordinarily frustrated with getting this to work. I've searched the forum to the point of a headache. Something about the .inf file and hardwar id's. I've uninstalled and reinstalled the drivers a million times. I've even reflashed the stock rom. Can anyone help? usb debugging works and PTP works. Currently back to stock and all drivers currently uninstalled.
Click to expand...
Click to collapse
Check this: http://forum.xda-developers.com/showthread.php?t=2391236

Thanks man but I've tried following that post. It doesnt makae sense that none of these work arounds work for me

mta1981 said:
Thanks man but I've tried following that post. It doesnt makae sense that none of these work arounds work for me
Click to expand...
Click to collapse
Ok, I decided to use a laptop which has never had my N7 attached to it as MTP, only as adb for wugs (before I got comfortable with doing things manually), I had the same problem you did, this is what fixed it. I had used koushes adb driver installer on it, so his driver kept intercepting it.
First I got these drivers and unpacked them: http://developer.android.com/sdk/win-usb.html#
Then I plugged in my device, with PTP enabled and updated drivers and browsed to those drivers and let it install...this did not fix it.
Disable usb debugging, plug it in, enable MTP, then go into device manager, then go into the menu and show all devices, you should see something like Google ADB driver, right-click and uninstall it, selecting delete driver checkbox, then reboot your nexus 7 while still plugged in, it should redetect your N7 as a "Nexus 7" and you should see it in Computer as a Portable Media Player, then unplug the device, wait 3-4 seconds to make sure its unmounted, then plug it back in, you should now actually see files.
NOW, once I saw that that worked, I noticed PTP stopped working, leave it plugged in, switch to PTP. then you will see the ADB driver back, uninstall it again, reboot the device leaving it plugged in, it will redetect the device again, it will say MTP again even though it's in PTP, let it finish, then unplug the device, wait a few seconds, and plug it back in, now you should be able to see it connected as a camera, and should be able to see files, now I can switch PTP ro MTP and back again with debugging off resulting in it working fine.
NOTE: USB debugging only works right in PTP mode for me.. which is fine, I tested to make sure that once debugging was off, I can unplug the device, and plug it back in and I can still switch between MTP and PTP perfectly.
EDIT: Actually I am now going to try leaving debugging enabled, in MTP mode, uninstall the ADB driver and reboot the device and see if that fixes that problem too.
EDIT2: AND IT WORKED!
So now I can have debugging on and off, in MTP and PTP mode, adb devices works perfect for either mode.
In summary, i think the REAL trick here is to put the device in each mode combination one at a time, delete the device and driver from device manager and reboot the device while it's still plugged in, then unplug the device and plug it back in, you do this for every combo outlined below, a total of rebooting and unplugging/plugging in the device 3 times...because PTP+debug on or off worked already
MTP on - Debugging off - find entry in device manager, uninstall it, reboot device, leaving it plugged in, verify it shows in Computer, unplug device, wait 3-4 seconds plug device back in, verify you can see files.
PTP on - Debugging off - find entry in device manager, uninstall it, reboot device, leaving it plugged in, verify it shows in Computer, unplug device, wait 3-4 seconds plug device back in, verify you can see files.
MTP on - Debugging on - find entry in device manager, uninstall it, reboot device, leaving it plugged in, verify it shows in Computer, unplug device, wait 3-4 seconds plug device back in, verify you can see files.
..at the end you should be able to have MTP and PTP fully working with or without debugging on.

Try installing Sony PC Companion. It will install the necessary drivers. Works great with my Nexus 7 when connecting to PC in Windows XP .

I'm on WIndows 8.1 and when I connect my N7 2013 to PC, it gives me error Unknown USB Device (port reset failed). Anybody knows how I could fix this issue?

hussam91 said:
I'm on WIndows 8.1 and when I connect my N7 2013 to PC, it gives me error Unknown USB Device (port reset failed). Anybody knows how I could fix this issue?
Click to expand...
Click to collapse
Good luck with that.

mtp
ive had my n7 for couple months now and mtp never worked only ptp until about a week ago when in cleanrom thread here http://forum.xda-developers.com/showthread.php?t=2383146&page=389 post 3877 asked 3888 answered. I checked in android devices and did not have the android composite adb interface. so I simply unistalled the drivers I had and plugged in device and bam. working great since. don't know if it was related but the day before I updated my sdk and there were some google drivers in the update list. hope this helps someone!
I don't mind airdroid as an alternative but soooo much nicer to plug in and drag and drop!! GL!!

USB charges but no data

Hi, my phone stopped being able to get a USB data connection. The port is physically intact and does not wiggle. I've tried two different Macs and one PC, different USB-A to -C cables (all verified by Benson Leung). Also toggled USB debug, MTP and PTP modes from Developer Options, rebooted phone and computer. When I plug the phone in, it only goes to Charging mode. Android File Transfer doesn't see it and 'adb devices' comes back empty. There is no notification offering me to select connection type. Did I miss anything or is it time to send it in? Thanks, Tony

What OS are you running on your Windows - checking your Device Manager under Control Panels - are all the Google / N5X drivers installed and working correctly before this ? Try uninstalling, reboot PC and re-install them - and, use different USB port to connect the cable (what kind of connections are you using ??)
Can you run ADB ?

Thanks I'm primarily using a Mac (10.10.5) but the PC was running Vista. It was a borrowed PC so I didn't install the drivers. I don't think it's a driver issue though since nothing shows up in device manager and the phone doesn't offer to switch out of charge-only mode. Also the same Mac worked previously.