The T-Bird migration instructions specify: Restoring to a different location If the profile folder names do not match or if you want to move or restore a profile to a different location, do the following: 1. Completely close Thunderbird, as explained above. 2. Use the Thunderbird Profile Manager to create a new profile in your desired location, then exit the Profile Manager. Note: If you just installed Thunderbird on a new computer, you can use the default profile that is automatically created when you first run Thunderbird, instead of creating a new profile. So, where is this "profile manager" located??