Recently I've been having a problem. I have the MBP in my sig, and have Lion and Windows 7 x64 installed. Both were working fine, but I haven't logged into Windows for a few weeks. Now, when I restart into the Option menu (where you can select the OS to boot to), I select Windows and it just freezes on that gray screen with the OS icons. I've used Windows for years, but on a Mac I have no idea where to start. I can't boot into Safe Mode, as Windows never starts. I'm guessing it has something to do on the Mac-specific side of things, but I have no idea how to troubleshoot Windows starting issues on a Mac. My setup is an SSD with two partitions (OSX/Win7) and a HDD with two partitions (OSX home folder/Windows NTFS storage). Lion is working fine, and I can access data from the NTFS drives from within OSX. Some recent changes that I thought may be an issue are the recent EFI update and a system clean from OnyX. If anyone has any ideas besides reinstalling Windows (as a last option, I'll have to do that but would really rather not) please let me know!