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My wife is using the newest version of Thunderbird - recently up-dated.  

Upon the new version being installed over the older version, she is no longer able to log on to her in-boxes because the app no longer will accept her password.  

The real problem is that the error message does not specify which password it requires.  

Is it her computer log-on password?  Is her eMail in-box password, is it something else altogether.  

We have tried all of the above (all eMail and log-on passwords) and none of them work.

There (We use Macs) The Keychain passwords are correct.  We have verified them.  So the installation changed something.  What do We do. 

I will not upgrade my account until someone clears this up.  I can't afford to lose my eMails!