Microsoft has released Microsoft Windows 2003 Service Pack 2 for both 64–bit and 32–bit editions. It is flagged as a high priotity update meaning that if you have your box set to automatically apply updates you will likely be seeing this message just as your server is rebooting.
We got a bit blind-sighted by the decision to release SP2 today. Usually major service packs are announced well in advance. Will update when I find out more, in the meantime carry on with due dilligence and proceed carefully.
Update: SP2 has since been moved off the High Priority list.
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