Just had it stall again at 1600 messages I had -- cleared cache, compacted all folders, restarted. No error message this time, OTOH when I started downloading again I didn't get an error message this time; let's see what happens.

EDIT --deleted a bunch of things manually from USA.net web interface to catch up with what was already downloaded/what hit as "downloaded" on IMAP. Was able to reproduce error that I got after only 7 messages downloaded -- froze again, restarted T-bird , and this is the message I got (see upload)

Sorry for some reason last reply didn't post. I restarted T-bird, got a bunch more messages -- these "hit" as IMAP and were moved to trash automatically when I went to the USA.net interface. Then it froze again after 1500 messages. Went back, quit Tbird, logged out of USA.net online, got back in to Tbird, started download again and this time only got 7 messages. Same thing RE rinse repeat but this time when I tried to download anything I got this error (see upload)

Maybe a timeout thing with USA.net?

Thanks again. Stumped. Have had that account for more than 20 years; periodically it acts up but this is new.

Quick edit: Domain shows as usa.net but I have to log in at netaddress.com if that helps.

Do you have an antivirus that scans your disk when files change? like what Thunderbird downloads email and opens and closed the same file loads and loads of times.

There is a bug floating around, but this sounds more like file contention brought on by frequent opening and closing of a file where two competing applications are slogging it out. Thunderbird might open the inbox file thousands of times to download thousands of emails. It depends on the protocol in use and the folders they come from among other things. But check in setting that you do not have allow the antivirus to scan incoming mail selected. This writes a temp file for each incoming mail and then copies it if the antivirus does not clobber it. That might be tipping things over.

OK, tried throwing out a bunch of stuff, got Inbox down to a modest 500 messages. It still stalled out at 200. Had Norton turned off and everything. Now what? Sigh. EDIT it redownloads items that were already downloaded but won't go past to "new" stuff. It's like something isn't registering on the IMAP side of USA.net. How should I phrase a ticket to them? Thanks!

First a correction -- doing POP not IMAP. For some reason last reply didn't show; shaved my InBox online down to 500 messages and it still stops after about 200 and when I log in to USA.net online, I don't see them as having "registered" that the message was downloaded. Tried turning off Norton etc.