Win7 dropping external sata drives after it goes to sleep
I have a tower computer with two internal sata hard disk drives (one with VISTA installed, and one with Win7 installed), one internal sata DVD RW, and two external sata hard disk drives. The internal sata HDDs are boot drives. I use the change the ROM to boot one internal drive Win7 or the other for VISTA. If I boot to VISTA I get the VISTA drive as the internal C: boot drive, D: DVD RW, E: and F: external drives, and the WIN7 internal drive is G:. If I change the ROM and boot to WIN7, I get the WIN7 drive as C:, the DVD RW as D:, the external drives as E: and F:, and the VISTA drive as G:.
If I boot to VISTA, all of the drives are listed in Windows Explorer, and they stay there, even if the computer goes to sleep.
If I boot to Win7, all of the drives are listed in Windows Explorer, but if the computer goes to sleep, the external drives become unavailable. After the computer wakes up, the E: and F: drives may or may not appear in Windows Explorer. If they do, and I select one of them, the computer begins to search the drive, and then the drive disappears from the list. If I open a cmd window, I can change to the E: or F: drive. I can do a DIR command and get a listing of the drive, but then when I open Windows Explorer, the drive are gone. When I go back to the cmd window, the drives are gone.
What do I have to do to prevent WIN7 from dropping the external SATA drives after it goes to sleep?