edwalt's - Things I Wish I'd known about SBS 2003....
1. Are you using etrust anti-virus? - Yes <See Below>
2. If you are NOT using etrust - Most likely LASSRV.B -http://www.symantec.com/security_response/writeup.jsp?docid=2006-082409-3922-99&tabid=3
If the answer is yes to etrust, then most likely the issue is with the latest etrust update.... The issue lies with a signature file that was released this morning that has some issues.
Here are some of the symptoms:
Please follow these steps at your own risk!!!!!
Boot into Recovery Console - If this is a Dell server using OEM media most likely Recovery Console will not be available. If this is the case please boot to Recovery Console using an XP CD.
Copy LSASS.EXE back onto the \windows\system32 and \windows\system32\dllcache
(Get lsass.exe from SBS CD #1 i386 folder using a different machine, you have to expand the file (expand <cd>\i386\lsass.ex_ a:\lsass.exe)
(You can also get lsass.exe from another working system).
Once you have LSASS.EXE back in the required locations, you need to disabled Etrust AV before rebooting.
After you are up, you need to get the latest signature files before enabling the AV services.
CA states that their signature 303.3056 is fixed.