RAID Manager doesn't Recognize Drive

I’ve been using two 2-TB MyBook drives for more than a year without problems. Each is configured to RAID1 for ~ 1TB storage space each. For the past few days ago, I keep getting periodic messages about one drive having a problem:

"WU2T12063832 has a problem.

Run WD WAID Manager for more details and contact technical support for help."

When I run RAID Manager, the referenced drive doesn’t show up. The other drives does show up as healthy. When I hover over WD in the taskbar, the referenced drive shows up as:

Temp →   Unknown

Status →   RAID1-Unknown

Interestingly, the drive is still recognized by my PC and still works perfectly. Only RAID Manager is having problems recognizing and controlling it. Does anyone know what’s up?

The disk you identified is probably bad. I assume you have a two disk system. One disk is operating fine that’s why it looks normal in windows. Check to see if the unit is under warranty and get the drive replaced asap.

How do I tell which drive is bad?

Looking over this manual (, the unknown status doesn’t match any of the described. I’m now wondering if it’s the RAID controller that has malfunctioned. This would explain the drive working, but RAID manager can’t get additional information about the RAID status.