Loosing IMAP emails

Hi all,

I've been having some trouble with Thunderbird Portable loosing my IMAP emails when moving from computer to computer. As as home I'm on dialup, when I'm at uni I use thunderbird to save all my emails to the flash drive for offline usage. However, when I get home, I can view the emails in Thunderbird the first time I run it, but the second time I run it, it looses all the folders and emails, but the data files are still in the profile directory. I've tried copying the profile across to an installed version of Thunderbird, as well as another copy of Thunderbird Portable, to no avail.

When looking through the profile files, I noticed that prefs.js, compatibility.ini and extensions.ini still had references to drive F:, which was the drive letter assigned to the flash drive by the uni lab computer, whereas my home system assigns it R: (by choice). Could this be the problem? Changing this to R: in all the files where F: doesn't appear to have worked. This problems appears to be in all the 1.5 series of Thunderbird (Portable), and I don't know if it existed earlier. Any assistance would be greatly appreciated, as this is driving me mad!

regards,
Peter