I have the strangest issue with a client, actually have never seen this before.
When she opens files off a file server she'll be working on them and she may take a break but leave the file open, then Office 365 Word, Excel, etc, will switch the file to read-only mode out of nowhere. I've tried everything humanely possible that I can think of.
Client PC is running Windows 10, 1809. Server is 2011 SBS. No one else is having this issue. The laptop is using BitLocker encryption. Could it be something with that?