Latest version of T-Bird installed ( 115.7.0 ) on a 12th gen i7 desktop. Have had a Hotmail acct for years, and I have had it in Thunderbird for years. Recently every time I open the client or get new messages I get the login failed box with options for retry, enter new password & cancel. I am still getting messages which is strange. I believe Microsoft has recently changed something in their security, when I went to hotmail website to make sure it wasn't the hotmail account causing this, it made me update some security stuff. I am connecting using IMAP and have double checked all ports and server names. Like I mentioned earlier This has been working for years with no problem until recently.