Following the release of this month"s Patch Tuesday updates, Microsoft issued a notification that the latest cumulative updates successfully fixed performance issues on certain systems with Windows Server 2019.
Microsoft acknowledged performance problems on Windows Server 2019 by the end of August 2024. The company then confirmed that the issue originates from the August 2024 Patch Tuesday updates, namely KB5041578. Affected systems would experience general system slowdowns, unresponsiveness, and high CPU usage, especially when running cryptographic services.
Initial reports and investigations showed that the root cause of the problem is antivirus software performing scans of certain Windows update directories:
After installing the August 2024 Windows security update, released August 13, 2024 (KB5041578), you might observe that some Windows Server 2019 devices experience system slowdowns, unresponsiveness, and high CPU usage particularly with Cryptographic Services.
A limited number of organizations reported that the issue was observed when the device was running an Antivirus software which performs scans against the ‘%systemroot%\system32\catroot2’ folder for Windows updates, due to an error with catalog enumeration.
Our investigations so far indicate that this issue is limited to some specific scenarios.
Here are the symptoms that affected Windows Server 2019 may exhibit after installing KB5041578:
- Show increased CPU utilization
- Experience increased disk latency/ disk utilization
- Indicate degraded OS or application performance
- Show that the CryptSVC service fails to start
- May boot into a black screen
- Experience slow to boot
- Freeze or hang
Now, with KB5043050, all those performance issues are gone. However, it is worth noting that the problem does not affect regular users with systems running Windows 10 or 11, Home or Professional—only Windows Server 2019 was hit.
You can learn more about performance issues in Windows Server 2019 KB5041578 in a post on the official Windows documentation website. Full release notes for the latest Windows 10 Patch Tuesday updates are available here.