Can you please offer some information about your setup because at the moment all I know is you have a computer and an existing password is not recognised. You have got a new/additional computer. '''Q: '''What type of OS, Windows, Mac, Linux ? '''Q: '''You have installed Thunderbird, but how did you install it ? '''Q: '''Did you download and install from the official website ? * https://www.thunderbird.net/en-US/thunderbird/all/ Or did you install via Microsoft app or Snap or Flatpak ? '''First make sure 'Thunderbird' has access to internet.''' * Exit Thunderbird. * Access Firewall - that might be default that comes with computer or it might be controlled by your Anti-Virus. * You need to set up Thunderbird as an allowed program to ensure it's not being blocked. '''Confirm -''' Thunderbird is set up as an allowed program. '''Q: '''Are you trying to set up exactly the same as you have on the old computer ? '''Q: '''Does this mean you want to backup the original data on old computer and put it into the new computer Or do you use Imap accounts, so just need to create an existing mail account on new computer ? '''Q: '''At this point have you created a mail account or not - regardless of whether it is working? You are obviously getting an error of some type which says 'password is wrong'. Please post an image showing that window and error message. A error with password may mean wrong password or it may mean password is ok but not for the username or password and username are ok but not with those server settings. I'm assuming you are trying to set up same account as on old computer. You say "Doesn't seem to recognise my manual configuration" Thunderbird has to provide the server settings, username and password which are accepted by server that maintains the account and emails, so they are very specific. However, at this point I have no idea what those server settings are supposed to be. But the following is used. 1. User name = full email address 2. Password is the same password you use to access your account via webmail. There are times when this may be different as some servers now insist on you using an app specific password. But as I do not know what server you are trying to use, I cannot say at this point whether that is the case. The window that shows you attempting to create a mail account with error message should provide enough data if you have not created mail account just yet. If you have created a mail account but get password error: '''On new computer:''' In Thunderbird * Help > Troubleshooting Information * Scroll down to 'Mail and News Accounts' * Copy all the data in that area * paste that data into this forum. Then I will understand what you are currently using for server settings on new computer. '''Then On old computer''' '''Q: '''What version of Thunderbird are you using ? In Thunderbird * Help > Troubleshooting Information * Scroll down to 'Mail and News Accounts' * Copy all the data in that area * paste that data into this forum. Then I will understand what you are currently using for server settings on old computer.