SP4 won’t integrate into RIS

I’ve been using RIS for a while now, and it seems to work reasonably well. At least until I’ve been trying to integrate SP4 into the picture. I ran update from the service pack to integrate SP4 into the flat install files. Everything looks good until I roll it out. The machine copies all the files over, then restarts, and stops with a “STOP C0000135 (Unable to locate dll)” stop error. Any ideas?