We have a Dell PowerEdge T110 at school and about a month ago one of the 2tb hard drives dies, it was sent away and replaced under warranty.

I replaced the hard drive when it arrived and am 99% sure I converted it to a dynamic disk and set the mirror off over the weekend, I was looking at the server today and noticed that only one of the two drives is showing and its a basic disk not a dynamic disk. I restarted the server after school today and looked at the SAS controller which shows the drive as being there but it does not show in Windows Server 2008 R2.

Is there anything I have to do to the SAS controller etc although I am sure it was there before but can't be certain.