Exchange 5.5

Exchange is running on a Pentium II, 450 Mhz machine. We upgraded the memory from 256MB to 512MB. After a reboot I get the following error “172 – System configuration Nonvolatile memory invalid – initialization aborted”. It still proceed to boot though. The event viewer gives me the following “System Information Insight Agent – Compaq Health Post Error Detected”. The services for Exchange does not want to start and I get “The dependency service or group failed to start”. At one point it did give me an error message of the RPC which I didnt write down though. Can you assist?