Windows 7: 7100 dual boot disk issue...

I am running Vista Business SP1 x86 on my system. It has three HDDs. A 74 GBB Raptor as my C: drive, a 300GB as by D: drive and a 1TB as my E: drive. I created a 110 GB partition on my 1TB "E:" drive and called it "W:". I then installed Windows 7 RC1 x64 on this "W:" drive.

While dual booting, I am seeing a recurring problem:



When I boot to the "W:" Windows 7 drive, I am told that my "C:" drive needs to be repaired and Scandisk repairs the drive (finds problems and fixes them).

When I boot Vista on the "C: drive, I am told that my "W:" drive needs to be repaired, and it does so (finds problems and fixes them)

If I reboot into the same drive, I see no error message. It only happens when I switch between operating systems.

After each "repair", the associated OS boots and all is OK. However, this is certainly not normal. I am concerned about what is happening... especially since the scandisk finds supposed problems.

Any idea as to why I am seeing this? Any cure?

System information:

CPU: AMD Phenom-II X4 810 (4x @ 2.6 GHz) | Mobo: ASUS M3N78-EM | RAM: 4096 MB (Kingston KHX8500D2K2/4GR) | Video: XFX - nVIDIA GeForce 8800GT (w/512 MB DDR3) | HDD1: 74GB WD Raptor, HDD2: 300GB 7200RPM Seagate, HDD3: 1TB 7200RPM Seagate | OS: Microsoft Windows Vista Business SP1 | Audio Out: BOSE Companion-5 (USB) | Audio In: On-board Motherboard | Monitor/LCD: SAMSUNG SyncMaster 245BW (24", 1900 x 1200) | Case: Antec 900 series | PSU: Thermaltake "PurePower" 700W, model W0317RU"| UPS: Belkin F6C900 900VA