Let's start with a full hard drive diagnostic - the extended one (takes a couple of hours) -- NOT the quick one.  F12 at powerup.

Thanks.  Running scans.  What next?

Hi JimmJimm,

To proceed with restoring the system to factory state you will need the username and password. If the above steps do not work, you will have to manually install the operating system. Please refer to the link below for installing the operating system.

http://dell.to/Wj9o0m

Note: You will need operating system reinstallation disk from Dell to perform the steps from the link above, if not please send me a private message with the computer's service tag, Name registered during the system purchase and email address so that I can check what can be done. To send a private message, click on my name and select start conversation.

The diagnostics were completed, everything was fine with one exception...A message at the end said this: No diagnostic partition identified.  

Hi JimmJimm,

The Recovery partition seems to be not recognized by the system. You will have to manually restore the Operating system on the computer using the link provided in the previous post.