"Enter password" - Samsung Galaxy TAB S SM-T800 suddenly locked and requesting password

[papadeltasierra]

Samsung Galaxy TAB S 10.5 WI-FI 16GB SM-T800

My tablet has suddenly started requesting a password at startup.  There is no PIN keypad (which is my normal way to login), just a ghostly text box with "Enter password".

I've tried every password I can think of and I can even login to the Samsung website using the account associated with the tablet.  However "Find my mobile" claims that the tablet is not on a network and it can't be unlocked or even made to ring.

Ideas?  Right now I have a large, expensive drinks coaster!

Thanks,

Paul DS.

[papadeltasierra]

OK, bizarrre and stupid bug it turns out.

My wife had been working from home and using Zoom and a Remote Desktop tool to access her work PC.  One of these was still running and when we started the tablet, this app requested a password and totally blocked all access to the tablet!