I’ve just changed my yahoo (mail) password. I’ve opened Thunderbird and clicked “Get Mail”. Instead of getting a warning telling me that the password is wrong, and asking me to insert a new one, I got this warning:

Sending of password did not succeed. […]

I got this error using Thunderbird 1.5.0.2 under Windows XP (no SP installed).

I googled around and found that some people had a similar problem: see [1] GmailForums: Can’t check/download messages with thunderbird 0.8.

Some people say that the solution is to delete the TB profile and to reinstall TB from scratch. I think that these people are simply crazy. It’s not a solution to reinstall everything from scratch just because you changed the password and TB doesn’t prompt to insert a new one (well, of course, this problem really suck but I guess it suck more to lose a lot of time to recreate your profile etc.).

Here the solution that worked for me:

1. If you have more than one e-mail account and you didn’t to a backup of your passwords, go in the “Tools” Menu > Options > Passwords > View Saved Passwords > Show Passwords > Yes > take a screenshot or write them in a safe place.
2. Close TB. Enter your profile folder and move these files in a backup folder: 12345678.s, cert8.db, key3.db (12345678 can be a different number for you).
3. Open TB: you will get prompted to insert the passwords for your accounts. I still got an error message “Sending of password did not succeed.” for my yahoo account, but I clicked again “Get Mail” and I received my messages. Now it works.

Explanation: TB will recreate the 12345678.s, cert8.db and key3.db files. In case of problems you can restore the files that you moved in a backup folder before (1).
My comment: shame on TB for such a bug that made me lose about 1 hour of work + another 30 minutes to write this guide for unlucky people that get the same issue. I was thinking that TB would be smart enough to recognize a wrong password and ask the user to insert e new one.