Android Studio: "Device is currently in the unknown state"

Question

I have an Android tablet and an old Linux notebook where I developed a program for months, no glitches.

Then I got a new Linux notebook, installed Android Studio, and tried to plug in the Android tablet. The tablet never shows up in the target list; it just says, "Unknown Device." When I select "Troubleshoot device connections," the wizard displays the ID of the tablet, with the cryptic message "Device is currently in the unknown state."

Turning the tablet's "USB debugging" option off and on again does not fix the problem. When I unplug and replug the USB, the tablet chimes, but does not put up a requestor asking if I accept this debugging connection.

Running adb devices returns:

$ adb devices
List of devices attached
adb server version (41) doesn't match this client (39); killing...
* daemon started successfully
B007904026445   no permissions (user in plugdev group; are your udev rules wrong?); see [http://developer.android.com/tools/device.html]

Any tips?

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Unplugging and plugging in the USB just one more time finally gave me the requestor on the tablet asking for permission to be debugged by this notebook. End of crisis.

An actual answer how to get that requestor without USB cable abuse would be nice...

Answer 1

while connecting Android phone to computer Select 'File transfer' option in 'Use USB for ' Dialog. this will solve the issue.Tested.