Win 7 lost from bootloader?

Hey guys, question for y'all:

I was running Windows 7 64-bit with a dual-boot configuration with Ubuntu 10.04. When I wanted to get into Windows I'd just select it from the GRUB menu upon booting up. Everything was working fine until (for a reason I still can't figure) Windows was dropped from the bootup menu. The partition Windows is on is still mountable and browsable from Ubuntu, so I am assuming it is not a hardware problem. I booted from the install DVD in the hopes of repairing Windows, but without a bootloader present, the disc doesn't know that Windows is there, and gives me a "StartupRepairOffline" error when I try to run its repair function. Is there any way to repair the bootloader without a full reinstallation? As far as I know the Windows files themselves are fine and workable.

Thanks!

If you cannot add Win7 back to GRUB bootloader, then uninstall GRUB, Boot the Win7 DVD or Repair CD, make sure Win7 partition is marked Active, run Startup Repair up to 3 separate times to write the System boot files to Win7 and start it up:

Startup Repair - Run 3 Separate Times
System Repair Disc - Create

Then install EasyBCD 2.02 to Win7 to add Ubuntu by name, drive letter, Linux type on Add Boot Menu Entry tab.

Sorry, quick clarification: how do I make sure the Win7 partition is active? The menu that appears allows me to choose which OS to repair, but none show up -- my options are to just hit "next" or load a hard drive driver, which I shouldn't need...

edit: is there a reason to uninstall GRUB manually? I understood that Windows just overwrites the bootloader, my first concern is getting Windows working again, worry about GRUB later

Partition - Mark as Active

Or use free Partition Wizard bootable CD which is the best tool for Win7 partitioning. You can mark Active and then from the Disk tab "Rebuild MBR" which may supplant the need to Repair. Partition Wizard

I.... sweet mother of mercy.

Booting from that disk iso and rebuilding the MBR worked perfectly. I'm posting from win7 now... I was looking forward to a long, long night of reformatting and reinstalling. You're a God among men, and I owe you a beer.

Nice. GRUB can corrupt Win7 to make it irreparable so it would be good to uninstall, or better yet wipe the partition it's on using PW CD.