Your master and media version isn't important in this case, but the client version is. What O/S and patch level, and what NBU and MPn level?
Rikki, the most common source of your problem is AntiVirus. You must exclude the VSP cache folder from your virus scanner.
To be honest, I don't feel like writing reams and reams about VSP all over again. I suggest you search through some older (but still recent) posts in this forum for some basic details about VSS and VSP, and also read the relevant pages in the manual. If you're really determined to sort the problem, then my advice is to invest in a few hours reading. HTH, kind regards, D.