well i have seen such an error before. however u may have a virus. there has been a number of nasties going around that cause such an error. do good check witha reliable virus scan program, norton usally doent work.
also if u get that error in win9x then that is a sure sign u have a virus
i only checked the system with norton antivirus pro 2003 with the newest virus definitions. So which virus prog would you recommend ?