Windows 7 - Thunderbird profile XP to 7

I have read several posts on this but they do not quite address my problem. When I installed Thunderbird on Windows 7, it, of course, created a new default. If I change the profile.ini to my old profile, the one I want, Thunderbird won't open at all and gives me the "already running Thunderbird" message. How do I point Thunderbird to the old profile (which I have in the Roaming folder right next to this new, empty, one)?

I wave my magic Google wand.....

Thunderbird Help: How To Manage Profiles

I guess the 3rd time is a charm. I moved the profile file again from old to the new computer, 3rd time, and this time, when I pointed the profile ini file to it, it worked. 5 hours later! These problems are frustrating but ok when I learn something. This time, I just kept repeating the steps exactly and finally, success!

I have no clue on XP.

But going from Tbird on Vista to Tbird on Windows 7, here is how I did the transfer with no issues:

Set the Vista installation to view hidden and system files.

Navigate to C users yourusername appdata roaming and look for a subfolder called Thunderbird.

Copy that entire Thunderbird folder to a safe backup location.

Install Windows 7

Install Tbird

Copy the saved Tbird folder to the identical location on the Windows 7 install. (NOT to C:\Program files).

That will overwrite the default Windows 7 configuration and restore your settings, email, and accounts to the way they were in Vista.

This may not help you if your XP install is gone, but for future reference it is a way to keep Thunderbird backed up and transferred as needed.

I always use MozBackup for that kind of stuff...

That program is GREAT, I've used it a few times with great success.