Microsoft fixed hundreds of security flaws in its September Patch Tuesday software updates — but it also introduced some annoying bugs. Now it has fixed some of them with a series of out-of-band updates. Excel 2016 users were among the victims, as Patch Tuesday update caused certain paste operations to fail. A hotfix in update 5002665 partly fixes the problem, but if operations still fail then users will have to resort to using Excel’s “Paste special” command instead. Users of Remote Desktop Services had found some instability in the application where RDP connections failed or where servers were left hanging at “Please wait for the Remote Desktop Configuration”. The issue was resolved with update KB5129194. Another issue that users were facing after the update was a problem with some Credential Guard-protected machine accounts. Some users discovered that they had lost some security within Active Directory which meant that some devices were not recognized. The solution involves temporarily preventing Machine Identity Isolation enforcement before installing a fix. Microsoft said that it would be introducing a permanent solution in a future update. Another issue raised by the September update affected applications that use HCS-managed virtual machines. In some cases, Plan9 users found that they were not able to access folders shared from the Windows host. Applications that depended on these shared folders sometimes displayed an error indicating that no Plan9 drive shares were mounted. Microsoft said that Claude Cowork and the Windows Subsystem for Linux (WSL) were two of the applications affected, while Hyper-V virtual machines that did not have the Plan9 feature were not affected. Microsoft also fixed an issue with USB Audio Class 1.0 devices. Some users found that no sound was coming from their audio devices after the Patch Tuesday update, and volume controls were unresponsive. Now restored sound, so affected users can once again make and take Teams calls. In addition to these fixes from the September update, there was also an issue for some users where they were incorrectly informed that Microsoft Defender had been switched off. This has now been resolved.