SATA hard drive wont show in my computer

Hi,

i have a 500GB samsung SATA harddrive that is full of data. When plugged in it no longer shows up in My computer as a drive.

Under device manager the device shows as connected and i can also go to disk managment and see the connected drive and the partitions on the disk but all options are greyed out apart from the ability to delete the partitions which i obviously dont want to do as i will lose my data.

This is being accessed on a windows 7 machine and has been tried with multiple machines which all do exactly the same.

Any help would be much appreciated.

Thanks, Phil