What kind of key to buy for non genuine OEM windows 7 ultimate

I bought this used desktop (compaq presario SR5310) with os windows 7 ultimate OEM about 8 months ago. Original according to the description on the desktop it came with windows 7 home premium.

Since a few weeks it says that windows 7 ultimate is not genuine. It looks like it's the blacklisted OEM Lenovo/IBM (original). This disk came with the desktop.
( see windows script host pic.)

Will a retail product key work on this OEM, or do I need to buy a new installation disk with product key.

Please help me to do this the right way.

You will need to buy a new CD key, which usually comes with a disk.

I recommend buying a new Windows 7 disk and key (whatever version you want) and reinstalling the OS.

~Lordbob