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The Windows partition has not been "lost". I have a 40Gb partition on the MBP. Disk Utility shows 40Gb with 2.68Mb of data and nothing else. What is "GPT and MBR"? I have not been booting into bootcamp. If the Windows OS is gone (as evidenced by only 2.68Mb of data recorded on the HDD) I don't see how bootcamp would work with no PC operating system.

Sure nice of Apple not to warn users that ML would wipe their Windows data. From what I have researched, OSX uses the free space for recovery so presumably that wiped the software?

Where would the Windows software be on my external backup drives? What files would I need to restore to the 40Gb partition to make it work or am I stuck having to run the Windows installer all over again so their boot sector would be installed?

Thanks for the help. Is there anything you can tell me about restoring Windows from the backup drive?