I have several times done clean install of TB 54.2 on my Win 10 laptop account settings on my Win 10 desktop. Desktop works fine; my original installation on laptop worked fine till a few weeks ago then stopped downloading my IMAP messages. On my laptop clean install I go through the email account setup procedure ("Create new account), Tbird comes to life, downloads about the last 10 days of emails, then stops. Sometimes (not always) if I exit TBird and start it again, it downloads a few more.

That's problem no. 1. Problem #2 is that I am unable to read any of the emails it does download. Sometimes one shows up on the screen but I can't do anything with it (like forwarding it or even erasing it). Does WIN 10 demand some different settings from Win 7? I notice also that on the Win10 laptop, the Edit menu (containing file properties) is unavailable (greyed out and italicized). Why?