11-9-2020 Problem: unable to sign-on to my existing Hotmail (HM) account in Thunderbird (TB). * Using the most up to date version (78.4.1) of TB. Running an Intel I-7 computer with Windows 10 professional. I also have a laptop using Windows 10 home version and the latest version of Thunderbird. ''The problem I'm describing below applies to both machines.'' Problem started with TB Ver. 68 and is the same in ver. 78. Background: Have had a HM account setup and working fine in TB until recently when I had to change the password. I am able to login to Hotmail webmail, but the password change didn't work in Thunderbird, repeatedly. Also able to sign into this HM account on my Android phone. *Finally deleted the account and tried to set up a whole new HM configuration in TB. I get an error message "Unable to log in to server. Probably wrong configuration, user name or password". There's nothing wrong with my username and password. In Thunderbird, I've tried both automatic and manual configuration neither works, with various server name, etc. I have attempted this with both instructions from the Thunderbird Help system and Microsoft instructions; neither work. I have three other email accounts on TB that are working, but I haven't thried any password changes. * Have other, non HM, email accounts in TB that are working fine. * Found: The server names shown in the Moxilla ISP database differ from those in the TB article on configuring HM. Neither work. * I have seen the help discussion of July 2020 where Matt suggested restarting the PC in Safe mode with networking to see if TB worked any better with HM. Did that: No change. * Also looked at my TB profiles. The Same profile name appears in both Local and Roaming, both with current date & time. Edited both Profiles to delete Pop, IMAP and SMTP entries for Live, office, Outlook etc. No joy.