Check that there are no leading or trailing spaces in the name or email address, and look in all address books, including Collected Addresses.

I suspected a bad character in the name so I deleted boththe good and bad names, including a search for that name in other address books. Then I manually re-entered the name. No luck. When I sent the message, it came back as undeliverable and added the bad name to the address book. There has to be something about that sequence of characters that creates a bad name. I'll have to experiment with other names to see what happens. Art.

Are you adding it looking like this

Yes, exactly like that. (I replaced the real address with "XXX" so the real person wouldn't be bombarded with Emails though). I deleated all entries in both collected addresses and address book. Then manually entered his address to my address book and sent a message using the stored address. It sent the bogus address and entered it to the address book entry in addition to my manually entered address. If I don't use the address book and just manually type in his address, it sends it OK. Therefore, it's something in the address book that screws things up but I can't find out why.

perhaps send me a private message with the actual email address as you type it. Like you I am guessing there is something that screws up the address book. but without seeing the address it is had to try and guess.

The actual address is Mike <517@outlook.com> Funny, now his address does not show up in my address book if I scan for addresses. If I type in just Mike, it does not show in the address book listing. But if I type in Mike H, then it pops up with his actual complete address in the listing. I never noticed that before. Art

I have my email copy so lets set this back to anonymized for the forum.

To test if the address book is corrupted, create a new address book from File/New/Address Book, then add the Mike contact, but add a character to distinguish it from the 'bad' contact. The new contact will appear in address autocomplete, so see if a message sends correctly without adding a contact with incorrect characters.

One symptom of a corrupted book is it doesn't accept changes, without any immediate indication to the user.

To repair a corrupted Personal Address Book (abook.sqlite in the profile), export it to LDIF format, close TB and rename abook.sqlite to abook.sqlite.bak, restart TB, import the LDIF file, drag the contacts from the imported book onto the Personal Address Book icon (or just leave PAB empty and leave the imported book as is).

Email name corruption issue solved. Remaining issue "not receiving Emails"still open. Problem: Cannot receive Emails. Hit "Get Message" and after ~ 20 seconds server replys with "connection to server mail.ee.net timed out." Sometimes it sends bulk Emails without me requesting them. First thing in morning, it usually sends me all Emails collected during the night automatically. Sometimes I get Email automatically without requesting one and never when I request one. The "bulk" download usually has > 10 Emails it it.

Host company says problem is not theirs & cannot do anything. They told me a log file would not reveal issue. Have POP3 account. Tried all Security settings. Host says to use security settings "none,Pass. Xmit. insecurely". Have Thunderbird 91.2.0. Tried another Windows 10 computer with new Thunderbird install. Emails received OK at web server only. It's the download from web to my computer that fails. My internet connection goes through a WOW server with separate Email account on same computer. Suspected interaction so I loaded a new Thunderbird program without WOW account on it. Still same problem. If I send Email from me using WOW account to me using Thunderbird account on same computer, Email received is OK on host server but not to Thunderbird.

Any suggestions I can try? Art Towslee