Windows 10 64bit Thunderbird 91.4 (64-bit) IPage (hosting) GoDaddy (domains) Norton Antivirus/firewall Update for TB 91.3.02 was recently downloaded and installed. Seemed fine for a few days. Yesterday morning my most important email address started refusing to send email. Error message "Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) smtp.ipage.com failed. The server may be unavailable or is refusing SMTP connections. Please verify that your Outgoing server (SMTP) settings are correct and try again." I went through all IPage trouble shooting steps - verifying settings, etc. Today I went through those again. When that did not work again, I uninstalled and reinstalled TB. I noticed along the way that after the initial Update and again after the reinstall, TB had removed all of my specific Outgoing server entries (by account). I re-entered them all. I removed several email accounts that no longer permit email client usage (att.com). TB send function still not working consistently. Every so often the send function would work immediately after I changed the Outgoing server. It did not seem to matter which I selected. Sometimes it would work for a few minutes, sometimes just for one email. I tried turning off Norton and turning back on. No visible effect. I tried removing and then re-adding TB to "trusted programs". No visible effect. This problem then migrated to all of the other email accounts (except gmail accounts). Now NONE of them can send reliably other than gmail. I can use the gmail server to send, but then TB changes the "From" field. I'd rather not do that as a work around. It will confuse too many people. I checked for updates. Updated to TB 91.4. I noticed that ALL of Currently, the "Send" function remains unreliable. For all accounts except gmail. If I go into Account Settings and change the settings, sometimes I can send an email right away, sometimes I cannot. Anyone with any clue what has happened or how to correct the problem please contribute a suggestion. Thank you in advance. JL