Users of Microsoft Outlook for Windows reportedly ran into numerous problems on Wednesday, after Microsoft issued a buggy—but critical—security patch.

As noted by ZDNet, users reported that the program became crash-prone after installing update KB3097877, particularly when loading HTML messages. In some cases users would see only a black screen when trying to log in. The problems reportedly occurred in all versions of Outlook on Windows 7 and Windows 8.1, but Windows 10 appeared to be unaffected.

“Had a fleet of mission-critical tablets break today because of this,” one system administrator wrote on Reddit. “Was not a fun morning.”

The good news is that Microsoft has since replaced the troublesome security patch with a new one by the same KB number, at least for Windows 7, Infoworld reports. The support page for KB3097877 confirms that the re-release should resolve any crashing issues.

Uninstalling the update should also do the trick, though users may not want to wait too long before reapplying. This week’s security patch deals with several flaws that allow for remote code execution, in some cases triggered by visiting a webpage with malicious code.

The impact on you at home: As far as buggy updates go, it’s surprising this one slipped through given that it affects all versions of Outlook. But at least it’s not as bad as last year’s update that in some cases prevented future updates.