I'd try:
1) update install: Control Panel, add or remove programs, Microsoft
Antispyware, change, update.
If that doesn't do it
2) remove Microsoft Antispyware. Delete all contents of installation folder
(typically c:\program files\Microsoft antispyware)
Be aware that this will remove all defaults set, and access to any
quarantined items.
3) reinstall Microsoft Antispyware
If none of that is enough, let me know.