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I'm having a huge problem with my android samsung galaxy tab 7".

Whenever I try to connect it to my computer, instead of showing normally in my adb devices, the name of the device is : ????? and it status is online or device.

I really don't know what is the problem, any help would be really appreciated. If you need more info, I would be happy to give it.

Ubuntu : 11.04

Device : Samsung galaxy tab 7"

Android version : 3.2 HoneyComb

I also added the rules in /etc/udev/rules.d/51-android.rules

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The '?' means that it can't determine the serial number , but adb may still work. The first thing you should try if it doesn't is to try a different USB cable/and socket. There are enough anecdotes involving Samsung devices to suggest that this is the problem.

You probably don't have adb over tcp/ip enabled but if you do turn that off.

If it says "no permissions", then that usually means a udev problem. If it works when you run adb as root then it is a problem with your udev rules: sudo /path/to/adb devices. One thing to watch out for with udev is that your computer needs to be rebooted for your changes to be recognised.

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Sometimes even with 51-android.rules, it may not work. I have the same problem, but adb sees my phone just fine, except for that. I run a program called Qtadb, and everything's there, but the bootloader, and serial number. I don't have to have the debugging notification running at all, just plug it in, and it works! I can do everything with adb that I want. When I run adb from a terminal, it recognizes that it's a device, but I get the ?????.... But it hasn't affected my work, it's just a nuisance.

What I'm saying, if it's working regardless, don't worry.

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Try this:

sudo adb kill-server
sudo adb start-server
adb devices

Please note that either you have adb on your path or you go to the platform-tools directory and then run these commands.

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adb doesn't require sudo and shouldn't be used this way. – user827992 Aug 11 '12 at 23:23

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