Business Windows users report deleted items in start menu and taskbar

Windows users, including within companies that use Microsoft 365 and Defender, may experience application shortcuts that spontaneously disappear from the start menu or taskbar. Microsoft has issued an advisory to contain the issue.

In a explanation sent to admins, Microsoft says it has received reports that a particular attack surface reduction rule with the description ‘Block Win32 API calls from Office macro’ is responsible for this. In the meantime Microsoft recommends to set that asr rule to ‘Audit Mode’ to further limit the impact. It is also possible to enable disabled mode for the rule.

Microsoft reported rather that investigates the mentioned issue that may cause shortcut icons to not appear or work. The company has already indicated that it is investigating whether recent changes to Microsoft Defender are the cause of the problem. The problem appears to center on a recent Windows Defender update, specifically update KB2267602.

The proposed adjustment will not completely eliminate the problem and will at most prevent the problem from persisting. Microsoft has not yet provided a definitive workaround and no advice to admins on how to get the disappeared shortcuts visible and working again. Company say that a rollback has been initiated that could take several hours.