Microsoft mops up after Patch Tuesday broke logins, audio, Excel

Microsoft's September Patch Tuesday updates introduced several bugs, leading to login, audio, and Excel issues. To address these problems, Microsoft released a series of out-of-band updates. Excel 2016 users experienced paste operation failures, which were partially fixed by hotfix 5002665. However, users may still need to use Excel’s "Paste special" command for complete resolution.

Remote Desktop Services users encountered instability, with RDP connections failing or servers hanging at a "Please wait for the Remote Desktop Configuration" message. This issue was resolved by update KB5129194. Some users faced problems with Credential Guard-protected machine accounts, experiencing lost security within Active Directory and unrecognized devices.

A temporary solution involves disabling Machine Identity Isolation enforcement before applying a fix. Microsoft plans to provide a permanent solution in a future update. Another issue affected applications using HCS-managed virtual machines, causing Plan9 users to fail accessing shared folders, which sometimes displayed an error about no Plan9 drive shares being mounted.

Applications like Claude Cowork and Windows Subsystem for Linux, as well as Hyper-V virtual machines without the Plan9 feature, were not affected. Microsoft also fixed an issue with USB Audio Class 1.0 devices, where users experienced no sound from their audio devices and unresponsive volume controls. Sound has now been restored for these users, enabling them to make and take Teams calls.

Lastly, Microsoft resolved the issue of falsely informing users that Microsoft Defender had been switched off.