Hi maguyvr, If the problem is only happening with one specific message, there may be an issue with the message on the server. One workaround is to sign in to your mail using a web browser, and delete the message from there.

Thanks for your reply. I'm unable to download any mail at all. It just sits there for 5 minutes or so and then displays the message. The last time it happened I found some information about it by searching for "The DELE command did not succeed". I tried moving all the messages in my inbox, compacting my inbox and deleting as many messages as I could. Having no luck, I finally deleted Thunderbird and reloaded it. Now it happened again two weeks later. Very frustrating. If I use my web email program, I have no idea what message to delete.

If you're not sure which message is the culprit, here's a trick that will help. Move half the messages, then test the issue. If the problem still occurs, move half of the remaining messages. If the problem no longer occurs, you'll know which half contains the culprit. Keep on narrowing it down by halves until you're down to one message.

Thanks for your help, but I have decided to scrap Thunderbird all together. I have put in countless hours the last time it happened and now three weeks later the same thing. It's just not worth the hassle. I'm going to use EmClient instead. Tried it a while back and thought is was pretty decent. I used Eudora for years and really liked it but couldn't find anymore updates for it.

Good day to you.

Here it is July and I see no progress on this issue. I am having same problem. I was using Outlook, but it, too froze. I called MS for help, but their only suggestion was to delete Outlook 2010 (my version, unsupported) and switch to Office 365, a subscription product. Disappointed in MS, I decided to try TB, which almost worked, except for this problem, and no intelligent solution. Don't tell me none exists, because the browser-based mail doesn't have this problem. What is differen't about TB's interface with server and why can't it be fixed?

P.S. My problem is with server verizon.net (AOL). I have no idea who handles att.net - probably not AT&T. AOL too? AOL problem?

Hi m.rosenblum, Your issue may have similar symptoms, but it is likely a different cause/solution. You should use https://support.mozilla.org/en-US/questions/new where volunteers can get more details about your setup.

Because maguyvr has abandoned this thread and more people might start using it for their own questions, I'm going to lock it.