The discouraging update is detailed in full on Microsoft’s forums, Reddit and social media, where Windows 10 users are posting about the problems they’ve encountered (via Windows Latest).

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“Last night, the last thing my computer did before shutting down was installing KB4556799 and KB4552931. This morning, it BSOD’d [Blue Screen of Death’d] twice in 10 minutes,” one user wrote on Microsoft’s support page (opens in new tab).  “…there was a windows update last night and now I don’t have network connections, same issue saying my network adaptor isn’t working,” another people wrote in Windows Latest comment section. As is often the case with botched Windows 10 releases, users are facing a range of different issues, which makes it hard to pin down exactly what errors are being caused by update KB4556799. It’s also worth noting that not everything is experiencing issues, and some laptops are having more serious problems than others.  For example, several people have reported audio problems where the audio output source is randomly changing. That’s certainly an annoyance but it’s not as bad as the Blue Screen of Death others are encountering, or the temporary user profile bug that is deleting files, photos and documents. If that last problem sounds familiar, it’s because we heard similar reports in February after Windows 10 version KB4532693 launched.  As TechRadar notes, some people are reporting a flickering white screen after installing the update, others have had their font replaced and some systems are going back into Windows 10 S Mode. We’ve also read about KVM switches no longer working and people having problems logging into certain apps.  

Windows 10 KB4556799 bugs: What to do

The easiest way to fix your system after installing a broken update is to revert to an older version of Windows 10.  Before I walk you through those steps, I should stress the importance of backing up your system to save your personal files in case a Windows 10 update deletes them.  If you want to revert to an older version of Windows 10, open the settings menu by pressing the Windows icon in the bottom-left corner then click the Settings gear (or type “Settings” in Windows Search). Choose “Update and Security” from the main Settings page. On the left-hand side, make sure “Windows Update” is selected. Toward the bottom, you’ll see “View Update History.” Select it. Press the first option: “Uninstall update” and choose KB4556799.  Your system will restart and take you back to an older version of Windows 10. Hopefully, one without any of the problems caused by update KB4556799. 

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