On Friday afternoon, Microsoft wrote that it has implemented a full fix for an issue in Windows that caused application shortcuts to disappear from the Start menu or taskbar. Have multiple IT administrators detailed the problem on Twitter and Reddit this morning, and it appears to be related to a recent update to Microsoft Defender’s threat detections.

The issue affects businesses and organizations that use Microsoft 365 and Defender to protect against malware, viruses, and other threats. In a note for customersMicrosoft said it has received reports that a particular attack surface reduction (ASR) rule is causing the problems. Earlier in the day, IT admins attempted to work around the issue by setting the “Block Win32 API calls from Office macro” rule to audit only.

Microsoft says it has “reverted the rule to prevent further impact as we investigate further.”

However, the fix took hours to deploy before Microsoft announced it was fully rolled out at 4:46 PM ET. Now that the fix is ​​out, machines should be back to normal.

“This has caused a bad day,” says one IT admin on Twitter, in response to Microsoft’s acknowledgment of the issue. “Happy Friday the 13th!” joked another. IT admins have made an effort to fix the problem and bring back the shortcuts, with many having to tell their Windows users to manually launch their apps from where they were installed or by typing Start > Run and the name of the app. executable file to use.

Three IT admins who are currently experiencing the issue at their organizations confirmed this The edge that all shortcuts are gone – and not just those to Microsoft applications.

Regular Windows users and consumers are not affected by this strange bug and it will only affect managed machines within organizations. That’s still hundreds or thousands of machines within large companies that rely on Microsoft’s security for threat detection.

We’ve reached out to Microsoft to comment on the situation and we’ll update you accordingly.

Update, Jan. 13, 8:20 AM ET: Article updated with more information from Microsoft.

Update, January 13, 5:43 PM ET: Article updated with more information from Microsoft.