Restoring HP z400 to factory settings

[Beevor41]

A bit of back ground: I've been asked by a friend to take a look at an old HP Z400 with Windows 7 installed that he still occasionally uses for work to run older software that is no longer supported on later OS. Apparently he started it up one day and it blue screened, seemingly without any interference (he runs it offline and has done pretty much since the point of purchase in 2011).

I've run system recovery twice to no result. System diagnostics show that the hardware is functioning properly. I can boot in safe mode, but there is a limit to what I can do here. I've backed everything up and planning on performing a full factory reset, dependant on if the original install discs have been kept or if they even arrived with the computer (it was apparently delivered with software preinstalled).

Any thoughts on what I might be able to try to get this old beast up and running again before I try and wipe the slate clean would be much appreciated. Fair warning, I'm far from what one would call an expert. I've built a few computers in my time, but have never delved much deeper than that. Some hand holding may be required.

[wb2001]

@Beevor41 

Please define what you mean by "system recovery" .   WIN 7 has that built-in.  It does a full recovery back to day 1.  The other option, called a "restore point", attempts to take the machine back in time to a specific date you select. Sometimes that will fail.If you need replacement disk set, go here.     Here is a list of the Z400 product numbers that it works with.  The product number is on a label, see this example.