Earlier this month, Microsoft released a number of security patches for its software products as part of its monthly "Patch Tuesday". However, a problem with one of those updates has resulted in Microsoft re-releasing the patch to fix a problem that crept up afterwards.
Infoworld.com reports that the patch in question had the official name MS12-078/KB 2753842 and it was supposed to fix a security problem with Microsoft's OpenType Compact Font Format drive. However, after the patch was released this month, reports began to show up that certain OpenType fonts had disappeared in various programs, including PowerPoint, Excel, and others.
Microsoft admitted a few days ago, "The original version of security update 2753842 had an issue related to OTF (OpenType Font) rendering in applications such as PowerPoint on affected versions of Windows." It then released a new version of that patch that is designed to correct the font problems.
If you have already installed the patch on your PC, the Automatic Update feature in Windows should indicate that you will have to install this new version to receive the corrected security patch. By the way, the patch corrects an exploit that so far has not been reported to have been used by hackers.