I have a number of dual boot machines working fine with earlier versions of Fedora. After a Fedora 17 install I get, along with at locale file error message flashing up
error: invalid signature
Press any key to continue
And Windows won’t boot. Following the example in the bugzilla.redhat.com posting I made the change of adding
set root=(hd0,msdos1)
and everything works just as it should.