KB5079473: What’s Going Wrong and What You Can Do About It
Microsoft released KB5079473 on 10th March 2026 as part of its regular Patch Tuesday cycle. The update addresses between 58 and 79 security vulnerabilities, including two actively exploited zero-day flaws—so it’s an important one to install.
Unfortunately, a significant number of users are reporting serious problems after installing it. Issues range from slow performance and crashes to audio failures, graphics glitches, and broken applications. Microsoft’s official support page currently lists no known issues, but community forums tell a different story.
If you’ve installed this update and your PC is misbehaving, here’s what we know and what you can do.
What’s Going Wrong
Performance and Stability
The most common complaints involve general system performance. Users report PCs running noticeably slower after the update, with increased memory usage and reduced responsiveness. Some are experiencing crashes, hard freezes, and blue screens of death (BSODs) during normal use, at startup, or when resuming from sleep. File Explorer becoming unresponsive is often a warning sign that a full system freeze is coming.
Some users report the update failing to install entirely, with error code 0x80070306. Running SFC and DISM repairs doesn’t always resolve this.
Audio and Graphics
Audio driver conflicts are affecting VoIP and WebRTC applications—if you use 3CX, Microsoft Teams, or similar tools and your audio has stopped working properly, this update may be the cause.
Graphics issues include black screens, rendering failures, and broken GPU-accelerated applications, particularly on systems with discrete or hybrid graphics. Some Dell workstations are experiencing DXGI and Direct3D 11 problems affecting CAD software and compute workloads.
Applications
Progressive Web Apps (PWAs) are particularly affected. The 3CX desktop app running in Brave or Chrome is slow, calls aren’t connecting, and audio is missing. WhatsApp for Windows is failing to load for some users—installing the beta version appears to work around this.
Microsoft Store apps including Office, Calculator, Snipping Tool, and Notepad have stopped working on some machines. This seems to particularly affect Samsung Galaxy Book devices, though it’s not exclusive to them.
Gamers are seeing BSODs in titles including Fortnite, Elden Ring, and Apex Legends. The crashes appear to be caused by kernel conflicts with anti-cheat software such as Easy Anti-Cheat and BattlEye.
Secure Boot Errors
Some users are seeing the message “Windows Boot Manager blocked by current security policy” after installing the update. This affects systems with older BIOS or firmware. The cause is that KB5079473 replaces expiring 2011 Secure Boot certificates with 2023 versions—if your firmware doesn’t recognise the new certificates, it blocks Windows from booting.
The fix is to update your BIOS/UEFI firmware from your motherboard manufacturer’s website before reinstalling the update.
Samsung Laptop Drive Issues – Not This Update
There have been reports of Samsung laptops losing access to their C: drive after the update. However, this has been traced to a bug in the Samsung Galaxy Connect app, not KB5079473 itself. If you’re affected, check for updates to the Samsung software rather than blaming the Windows update.
What You Can Do
Check for newer updates. Microsoft may release a fix or Known Issue Rollback (KIR) for these problems. Keep checking Settings → Windows Update for any new patches that address the issues.
Roll back the update. If the problems are severe, you can uninstall KB5079473. Go to Settings → Windows Update → Update History → Uninstall updates. Be aware that this removes the security patches, so it’s not ideal as a long-term solution.
Use System Restore. If you have a restore point from before the update was installed, you can roll your entire system back to that state.
Update your drivers. The update may have overwritten or conflicted with audio and GPU drivers. Download the latest versions directly from the manufacturer’s website (Realtek, NVIDIA, AMD, Intel, etc.) rather than relying on Windows Update.
For gaming crashes. Try temporarily disabling Memory Integrity. Go to Windows Security → Device Security → Core Isolation and toggle off Memory Integrity. This reduces security but may resolve conflicts with anti-cheat software.
Update your BIOS. If you’re seeing Secure Boot errors, update your motherboard firmware before attempting to reinstall the Windows update.
Try a clean boot. Start Windows with minimal drivers and startup programs to identify whether a third-party application is causing the conflict. Run msconfig, go to Services, tick “Hide all Microsoft services”, click “Disable all”, and restart.
Run SFC and DISM. These tools can repair corrupted system files. Open Command Prompt as Administrator and run: sfc /scannow followed by dism /online /cleanup-image /restorehealth
The Bigger Picture
It’s worth noting that these issues appear to affect a minority of machines, often tied to specific hardware and driver combinations. Most PCs will install the update without problems. However, the number of reports is significant enough that Microsoft will likely investigate and may issue a Known Issue Rollback (KIR) or further patch.
The security vulnerabilities addressed by this update include two zero-days—flaws that are being actively exploited in the wild. This puts users in an awkward position: the update is important for security, but it’s causing problems for some. If you’re not affected, keep the update installed. If you are affected, the workarounds above should help until Microsoft issues a fix.
How We Can Help
If you’re a Trichromic client and you’re experiencing problems after this update, get in touch. We can help diagnose the issue, apply workarounds, or roll back the update safely while keeping your systems as secure as possible.
For businesses, we can also help you manage Windows Update policies to delay problematic updates until they’ve been tested more widely—balancing security needs against stability.
Last updated: March 2026