I installed Thunderbird 115.6.1 and it will not send or receive email. I uninstalled Thunderbird and scoured the Windows 10 Registry with CCleaner. When reinstalling Tbird 115.6.1 it works until I reboot then it fails again. I have checked the serer setting for the Incoming and Outgong servers and they are correct. My PC goes online without a hitch with Firefox, Tor, Vivaldi, and DuckDuckGo browsers. The Internet connection is solid. Note: Firefox was misbehaving in that it would not fully open some sights. In Windows Programs and Features I found and executed a Repair function for Firefox and that solved that problem. This saved me from uninstalling, flushing the Registry, and reinstalling. I thought it may clear the Tbird problem, but it did not. I am quite technically savvy as I used PC since they were on the market and never ask for help until I've exhausted every possible fox. This problem is one for the history books and eludes me. Error message is that the server is not responding. eMClient email software works without a problem as does using Web mail through Firefox or another browser. Your help is most appreciated, or a link where i may download a previous version of Thunderbird. Thank you, your help is warmly appreciated. Wayne English Wayne@WayneAEnglish.com WayneAEnglish.com