When I bought my new Dell Studio XPS 16 laptop, the first thing I did was take out the HD and put in a new SSD. Now I've put that original HD into an external eSATA enclosure and I'd like to use all of its space, but there was a parition on it called OEM Partition that was protected, and I could not delete it from the Disk Management utility.

To delete it, I simply ran diskpart.exe, which comes as a part of Windows 7 and I think Windows Vista.

With diskpart running, I first typed:

select disk 1

then:

list partitions

(to make sure I was on the right disk), then:

select partition 1

and finally:

delete partition override

...and that nuked it! In fact, I had the disk manager open while I did this, and it vanished before my eyes. Now I can make a new partition utilizing all of the space on the drive!