Thunderbird set up
I have used Thunderbird for years on an iMac (O.S Monterey 12.7.6) until now when it will not open. I have tried to download and re-set anew and while Thunderbird identifies the in and out servers I always receive the message "UNABLE TO LOG IN AT SERVER PROBABLY WRONG CONFIGURATION,USER NAME, OR PASSWORD'". My full name and email address are correct so I have tried every password I have ever used, without success. iCloud email works ok but I prefer the Thunderbird display. Please help as I do want to keep using Thunderbird which is a really good app. Thank you.