Had not seen this under Vista before...WD Mybook 500gb external usb hard drive keeps spinning down after a few minutes of inactivity, even while using the machine. Everytime I go to access the drive, I have to wait for it to spin back up. This can get annoying! I can't seem to find any power settings for this external drive while in use!Will enabling write cacheing prevent this possibly?Any help would be greatly appreciated!

Try this:Go into power options, click on "change plan settings" for whatever plan is selected (default is balanced), change advanced power settings, and adjust the setting under hard disk.I believe it works for both internal and external drives.Want to know if your hardware will work on Windows 7? Check out these links: **Windows 7 Upgrade Advisor ** **Microsoft Logo'd Hardware List**

Thats the first thing I tried...It appears though that enabling write cacheing fixed my issue!

I lied...it still happens, just less often. Power options are already set to not turn off hard drives.

I figured it out with some tinkering if anyone else is still having this problem. My WD 2TB HDD is plugged into the "Master" plug on my surge protector so it has to be active all the time for everything else to have power. b00st3d, you were on the right track, but on "Advanced Power Options", you have to disable "USB Selective Suspend Setting" under "USB Settings". Works like a charm, and I don't have to enable write cacheing (not recommended, I lost 1TB of data that way).