>>I've seen cases where FDISKing (repartitioning) the drive with the exact same partition size has restored access to files, but that's pretty rare. If you have to have these files (and can afford it) I'd take the drive to a data recovery service...
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>Thanks, for your reply. Fortunately I have backups of the important stuff. The loss of the other stuff will cause about 2 or 3 days of work. I guess bringing the HD to a recovery services will much be more expensive than bringing in the data manually.

Yes, it would. If it's not too late, you could try:

FORMAT C: /MBR

which I should have mentioned before. Again, this isn't a likely fix, but...