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I upgraded to Mac OS X Lion and I can't run the installed Windows anymore. It seems the issue is that the Lion installation created extra partitions so the Windows partition has a different number one. It's disk0s4 instead of disk0s3 (if I recall correctly).

Searching online found several discussions about it but only one with a proposed solution,, essentially:

bootrec.exe /FixMbr
bootrec.exe /FixBoot
bootrec.exe /RebuildBcd

which didn't work. bootrec.exe /FixBoot claims that no windows partition has been found.

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Unfortunately, I ended up re-installing. – Pablo Aug 1 '11 at 16:37

Maybe rEFIt would be of help to you? I had rEFIt installed from beforehand, and my laptop seems to have survived the Lion upgrade with dual boot intact.

You could try this first from a CD without permanently affecting your computer, and see if it helps or not.

share|improve this answer
That's a good idea. – Pablo Aug 1 '11 at 16:37

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