[Quelch]

I've been using calibre for three years and this is the first time I've had a problem
When I plug in my Nexus 7 calibre no longer sees it
Plugging in my wife's Kobo still works normally, listing the eBooks on the Kobo and I'm able to transfer eBooks to the Kobo as usual

The Nexus 7 is no longer seen by calibre or by my Windows 8.1 desktop computer though it always worked in the past
Apparently Google sent out an update that changed the driver for the Nexus 7, 5 etc on Windows 8.1 computers, obviously the wrong driver
On my Windows 7 laptop computer the Nexus 7 and the Kobo connect to calibre as normal
I've set the Windows update to not download updates on the laptop in case Google decides to send the wrong update for Windows 7 computers too

I suggest it may be a good idea for anyone using Nexus devices to prevent updates in Windows computers until Google sorts the drivers out