It sounds as if the " client" <pun intended> put you at a disadvantage, since she forgot to mention her "email client".
Normally moving a profile in TB is not a huge endeavor.
As long as TB is still installed on the old computer and the profile is still there, you should be OK.
There are "best practices" ways and there is at least one "cheat" way (by copying the entire Thunderbird folder from appdata on old computer to the same spot on new computer and then a few minor tweaks in the account settings). The latter has always worked OK for me (multiple moves from XP to Vista to 7 and then to 10 with the same profile!).
You did not mention if the two computers are on the same version of Windows and same the architecture (32-bit or 64-bit).
That information could be useful to know the source and eventual destination for the various folders.
- Install TB on new computer
- Copy/transfer/move TB profile from old computer to new computer
- Minor adjustments in account server settings so that TB can find the newly transferred profile in the correct local directory on the new system
In any event, it *might* just be a question of editing the profiles.ini file to point to the new location.
Have a look here -- these tend be rather nauseating in their level of detail, but they are accurate and time-tested:
Mozbackup is no longer developed/supported, but seems to work OK (just be mindful that it may not work 100% correctly on a large, really old or corrupt profile).
Always a good idea to backup the profile before trying any of this...
And there's this tool: http://www.nic-nac-project.de/~kaosmos/mboximport-en.html
That should be enough to get you started,
Edited by MoxieMomma, 05 December 2016 - 03:17 PM.