Windows System Executable Give UAC Prompt Showing Unknown Publisher

I was just about to go to bed when I logged in via remote desktop to to my Media Center PC to schedule a show to record when the Windows update notification popped up. I have it set to install updates automatically on Sundays, but since no shows were scheduled to record for the rest of the night I decided to go ahead and install the updates. After it was done and rebooted I logged in to check and make sure everything was OK.

Now when I run any system program (mmc.exe, task manager, etc.) that usually doesn't require a UAC prompt, I now get a UAC prompt showing publisher unknown. I have the Sysinternals process explorer installed, and when I run it as administrator it shows the publisher correctly as Microsoft Corporation. I checked and there are no errors in the event viewer.

I figured it has something to do with security certificates. I ran sfc /verifyonly and it finds errors, so I ran sfc /scannow and let it repair. After rebooting it didn't fix it though. Running sfc /verifyonly again it still shows errors, and running sfc /scannow this time and I get "Windows Resource Protection found corrupt files but was unable to fix some of them." In the CBS.log file there aren't any lines with "Cannot repair member file" in it, but there are a lot of other things.

Since this is a Media Center PC, it is recording TV shows daily, so I have limited time to do anything that requires rebooting or shutting down. I have to go to bed, I've already stayed up way too late. I won't be able to do anything to it until it's done recording tomorrow's shows. Unless anyone has any other suggestions, I suppose the first thing I will try is use system restore to revert to before installing the updates.

This is caused by update KB3004394. Uninstall it and your system will go back to normal.

Microsoft has pulled this update from Windows update.

Thank you!!! One of the reasons I have that system install updates on Sunday is just for reasons like this. I installed the updates on my gaming system Tuesday night and it is fine, so I figured it would be OK to install them. That system is Windows Home Premium though, and I just checked and KB3004394 is installed. I've learned my lesson and will stick to waiting for Sundays to install updates on the Media Center PC.

Now I wonder if I should uninstall KB3004394 on my other system or leave it alone since it's working...

I personally would uninstall it since there have been a variety of issues and Microsoft has pulled that update from its update servers. It is not a security update either.