Apparently, your computer is infected with the W32.Blaster.Worm or one of its variants.
This happened because you have not been using an internet connection firewall and have
neglected to install the critical updates available at the Windows Update website.
What You Should Know About the Blaster Worm and Its Variants
http://www.microsoft.com/security/incident/blast.asp
Are you looking for info about the cause of "Remote Procedure Call (RPC)",
initiated by NT Authority\System error message that shuts down Windows
(you might also see svchost.exe error occasionally)?
http://www.faqs.org/rfcs/rfc1831.html
--
Carey Frisch
Microsoft MVP
Windows XP - Shell/User
Be Smart! Protect your PC!
http://www.microsoft.com/security/protect/
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| I had a crash,reformatted my hard drive&now after 5 min
| or so online I get an error message: NT authority:
| Windows is shutting down because the rpc terminated
| unexpectedly. Windows XP then reboots.I never had this
| problem before,running XP about a year. Thanks for any
| help.