harddrives disappears

Any trick on how to get windows7 to keep seeing your drives?
I have tried un-sleeping, increased time to 999min. All drives have drive letters & are listed as active and healthy etc. Each have mix of ide but mostly sata drives. Windows have been updated.

I have a small office with 8 computers trying to run Windows 7 now. All fresh installs onto new sata drives @ 2 weeks now. (The old xp drives was just turned off awaiting reformat). Everyone is starting to have the same problem with drives that disappears. On some of the computers it happens as quickly as in 5 min after reboot.

Any clues?

Drives shouldn't just vanish. Even if the OS spins down the drive it will still show under My Computer, and wake the drive when accessed.

I had a disappearing drive issue with Western Digital drives quite a few years ago with XP. The replacement drive eventually started exhibiting the same behavior, and because it was the OS drive it would eventually blue screen the system.

Unfortunately I'm at a loss as to what to recommend for you, as it sounds like a general incompatibility might be the issue. If all the drives exhibiting this problem are the same brand/model(s) and they also worked fine under XP, then I would have to surmise it is definitely an incompatibility with W7. You might poke around the manufacturer's website and see if others are having the problem and if any solutions were posted.