Hard drive invisible after long "power off"

My hard drive (Western Digital 40GB WD400EB) is not visible after a long
"power off" situation, I mean when the server is off for a few hours.
My system is a Windows 2000 server SP 4.

Ive' noticed 3 things when my drive is invisible in explorer;

1. The drive is visible in the BIOS
2. The drive is visible in Device Manager
3. The drive is INVISIBLE in Disk Managment

The only way for me to solve it is by disconnecting the IDE cable to the
drive, rconnecting it and rebooting the system. Yes, weird...
Looks like the drive is in some sort of locked state...

If the drive is visible, then everything works fine; I can read AND write
data. The drive doesn't contain WD's EZ-Bios.
I've formatted and partitioned the drive a few time, but that didn't solve
anything.

Btw, the drive is Master on IDE-2 and contains no operating system, only
data.

IDE1 contains two WD drives, of which one contains the operating system.

I looked for days on Google and the web (including Western Digital's
support) but couldn't find any solution.

Thanks in advance