The information that your disk is fat32 or windows NTFS is stored outside the actual format area. You need to actually wipeout the primary dos partition to take out the backup registry. The program that does this is fdisk that shipped with dos 6.2. Microsoft no longer includes it in windows. Reformatting is an extreme step. I'd be sure you have everything backed up or you may loose it for good. There may also be another solution. Do you have mail you want to save? Do a search for *.mbx and *.toc you should find files called in.mbx, in.toc, sent.mbx, sent.toc... and they should be located in your mail program directory. copy them out somewhere else and you can load them back over a new install and save whatever is currently in your boxes. Do you have Norton utilities? If so you can uninstall the mail program then reboot and run windoctor. This should find and delete the registry entries that no longer link to anything. Reboot again and reinstall the mail program. Copy the old boxes back onto the new and you are good to go. If you back the mailboxes to CD you will have to uncheck the archive bit on the files or you won't be able to write new mail to them. Right click on the files then select properties. Click in the checked archive box to uncheck it. You can only do this when the file is off the CD and back on the drive.