Rod, this Microsoft Knowledge Base Article 301224 may offer some insight into your problem:
Best of luck,
Win XP, I wanted to revert back to an earlier time. I put in an older program that doesn't agree with XP. I took it out but I still get a warning. Sys restore has not created any restore points and it's turned on.
The older systems you typed scanreg /restore to find a known good restore point. It's seems it's not available on XP. Any suggestions? Thanks