a flashing folder with a question mark on it after trying to install Win7

I just got Snow Leopard and decided to also try out Windows 7 via bootcamp, because I heard Snow Leopard supports this. Now, after partioning the HDD and starting the setup, all was fne, but after the windows setup files had been "expanded", the setup needed a restart.

Now the computer starts with the chime and then displays a flashing folder with a question mark on it. It flashes for a while and then it displays a black error screen saying that there's a problem with my Win7 install (it's a Windows error screen, not an OS X one). My only options are to look at that error screen or start the setup again, because it will boot to the Win7 setup DVD.

I've tried everything from booting in safe mode (shift), forcing to boot from the 10.6 install disk (c) to reseting PRAM (cmd+opt+p+r). Nothing works, it always flashes to folder a few times and then displays the error screen.

I'm guessing the Win7 setup overwrote something crucial in the OS X boot sector, but I'm not all that tech-savvy to be sure.

Have you got any suggestions or advice for me?

http://www.mac-forums.com/forums/os-x-operating-system/162425-flashing-question-mark-start-up.html

Before you post a question, it's always good to read up on the stickies.

UPDATE

I ran the Win7 setup again, this time it continued after the restart.

Now when starting the computer, it still displays the flashing folder, but after a while, it boots up in Windows. I noticed this only happens, when the Snow Leopard disk is inserted, otherwise the folder flashes endlessly.

I can see and access my files on the Mac OS partition and nothing seems to be lost, but now, when I a have actual access to my computer, can I somehow just reset everything and install a fresh Snow Leopard? Keep in mind that I can't boot from a the SL DVD, only Win7 or Win7 setup DVD. Maybe something with a Linux live CD?

Also, I've read through the stickies, none of the things I tried helped.

When you tried to boot from the SL DVD, did you hold down the C key right after the StartUp Sound?

How are you seeing your OSX files in Windows 7?

I pressed C right after the chime. It has no effect. Same with Shift, S, D, X and Cmd+Opt+P+R.

The new bootcamp that comes with Snow Leopard has Windows Drivers for HFS+. It's read-only, but still handy.

If you hold down the OPTION key between Command and Control right at or after the startup chime, does a boot menu show up?

I'd really like to take credit, but I honestly don't know what I did.

Anyway, after fiddling around with the Windows' settings, it required a restart, and indeed, suddenly pressing the option key brought up the boot menu.

Now I have a working dualboot with SL and Win7