When it is necessary to shut this computer down, it can be very difficult to get it up and going again.

I get the following message: "c:\windows\system32\config\systemprofile\desktop
refers to a location that is unabailable.

I am running Vista Home Premium 64 and do have the Vista disk. The computer will start up sometimes on the first try and then most times after several several annoying tries. The computer was put together with new and old parts. The hard drive was new the other drives are old. New mother board and graphics . All help would be appreciated.
Thanks,
John