Android 6.0. Nexus 7 tablet. Problems

[Derfs Nexus 7]

The tablet updated to Android 6.0 a few days ago.
Now, the USB port is disabled whenever the lid is closed.
The USB port selects 'Charging Only' (no data). when the lid is opened.

Also, Windows 7 keeps opening and then closing a window (over the ones that I am using) for the Nexus 7, every few seconds.
When using the Windows 7 laptop to look at the files & folders on the tablet the window auto closes & reopens making copying files to/from the tablet v difficult.
Any idea how to stop this happening. Also, how to select Charging & Transfer files (MTP) on the USB port so that it stays selected, as in earlier Android versions ???

 

[B. Diddy]

Welcome to Android Central! When you first connect the tablet via USB, and the tablet is awake, swipe down and tap the USB notification, then select MTP. When the screen goes to sleep, does the connection go away on the computer?

 

[Derfs Nexus 7]

When the screen goes to sleep it is still available via the window on the PC. However the window on the pc is opening and closing (i.e. appearing and dissapearing) every few seconds with the windows warning being flashed ''USB device not recognised. One of the USB devices attached to this computer has malfunctioned, and Windopws does not recognise it.

While wishing to assist you in diagnosing this bug I need to return to the previous Android operating system so that I can use the tablet. In its current condition I am unable to transfer files to the tablet from my PC. How do I return to the previous operating system ??

 

[B. Diddy]

Try wiping the cache partition, which won't erase any personal data: http://forums.androidcentral.com/go...e-nexus-7-2012-2013-cache-partition-wipe.html

If you really want to downgrade, you can manually flash the firmware: How to manually update your Nexus | Android Central