I copied an old TB profile from an old Windows XP laptop onto a Windows 10 PC. I readup that you should create a new profile using the Profile Manager and copy the old files into the new profile. I did that and then changed profiles to it. It opened as if it was a brand new Thunderbird installation with nothing there. How can I get back to my original prfile as there is no File menu with the option? I'm currently using a version of Thunderbird on another Windows 10 laptop to get and receiver emails, but I'd like to get the PC sorted.