I installed Windows 7 over Windows XP and forgot to backup my emails. I still have the Thunderbird profile folder saved in
Documents and Settings though.
How do I go about recovering all my mail and messages from the profile folder?
Based on About.com's How to Restore a Mozilla Thunderbird Profile from a Backup Copy:
To restore your Mozilla Thunderbird Profile from a certain location:
First, create a new profile in Mozilla Thunderbird. You will overwrite this new profile with your data you want to recover or copy. If your current default profile does not contain any data you want to preserve, this step is not necessary, and you can overwrite that profile
Now, it's time to copy the files:
If you created a special "Restoration Profile" profile, you can rename it after the process above.
I just had the same problem, I followed the indications in mozillazine:how to move your profile and worked wonderfully. Short version:
Please note that if Thunderbird shows partial data or some folders appear empty when they shouldn't, it might be due to other reasons