I have a user with Mozilla Thunderbird and we just put in a GMail account into his configuration (to add to what was already there).
He now has duplicate "folders" in his Inbox despite having only one account with that name. How do I fix this?
I found this question but he doesn't have disappearing emails, just duplicate accounts.
I'll try rebuilding the index (recommended in that question) but I don't know if that will help.