0x00000050 in ntoskrnl.exe after SP3

I had a computer that went down due to a:

0x00000071 SESSION5_INITIALIZATION_FAILED

No information worth anything was found so I decided to do a repaired Windows 2000 Installation. This got the machine to work BUT all of the applied updates previous to the crash weren’t there anymore. I began installing them. Once I installed SP3, I got the:

0x00000050 PAGE_FAULT_IN_NONPAGED_AREA ntoskrnl.exe

I followed MS instructions to check the drive and nothing was wrong. I then tried Safe Mode. I can boot up into Safe Mode fine and if I uninstall SP3, all works again as well. Has anyone encountered this and gotten it resolved? Thanks, Jeremy