What Files Are These?

From: MAH (anonymous_at_discussions.microsoft.com)
Date: 05/26/04 

Date: Tue, 25 May 2004 19:11:37 -0700

My antivirus software keeps trying to block these files
from accessing the internet:

c:\windows\system32\winst.exe
c:\windows\sysupd.exe
c:\windows\system32\wbem\wmiprvse.exe
c:\windows\system32\terrabyte.exe

Are these bad files? Or, are necessary for my computer?
Should I block them, or, give them access?

Thanks!