Read this first: http://blogs.technet.com/b/srd/archive/2012/10/09/security-advisory-2749655-and-timestamping.aspx
One of the date/time stamped screwed up bulletins is the Exchange one.
Microsoft Security Bulletin MS12-058 – Critical : Vulnerabilities in Microsoft Exchange Server WebReady Document Viewing Could Allow Remote Code Execution (2740358):
They are rereleasing Exchange updates due to that sign thing.
“We will re-sign and redistribute all files and packages affected by this issue. Today, we are re-releasing an initial batch of four security updates — MS12-053, MS12-054, MS12-055, and MS12-058 — with new digital signatures, each of which has been timestamped with a proper timestamping certificate. We are continuing our investigation and expect to re-release additional bulletins as needed in months to come.”
Assuming you are insane enough to install this one today , remember this sucker takes a lloooong time. Do not stop the install in the middle of the install.
And remember this tip: