Although many users may not notice them, Microsoft often releases more than just security updates in its regular bug patching cycle. However, they are frequently not released at the same time as security patches.

Microsoft (NASDAQ: MSFT) released several non-security updates for Windows 7 and its server counterpart, Windows Server 2008 Release 2 (R2) two weeks ago.

The main purpose of four of those patches was to improve stability and reliability of the two operating systems. Unfortunately for an undetermined number of users, one of those updates broke their systems rather than make them more stable.

The problematic update is Microsoft Knowledge Base article KB977074, which is creatively named: "An update is available to improve the stability and the reliability of Windows 7 and Windows Server 2008 R2."

Within a day or two of the updates' release, a problem thread began on Microsoft's TechNet user forums.

Several posters to the thread complained that after they installed update KB977074, their systems would hang when they went to reboot. Uninstalling it was the only recourse.

"Windows Update installs the KB977074 update, but after rebooting my system hangs," a user with the screen name "Dunghoaxinh," said in a post. That user was joined by another nine complainers, all with the same problem.

Meanwhile, technology enthusiast site Ars Technica, which apparently spotted the first complaint thread, also spotted a second TechNet thread for users who haven't been able to install the update at all.

"I have tried to install the current update. It fails to install. I have tried using the auto update. It failed. It also failed going to MS downloads," wrote one frustrated user who goes by the screen name "Super Sarge."

According to Microsoft, the problem so far is not widespread.

"We have not seen this as a major issue within our customer support channels; however, we are aware of it and are working to identify the cause," a Microsoft spokesperson said in a statement e-mailed to

"At this point, there is no indication that this specific update is the cause of the install issues. We will share more information when it becomes available," the spokesperson added.

Translation: there is no fix yet.

Stuart J. Johnston is a contributing writer at, the news service of, the network for technology professionals.