[German]On March 31, 2026, Microsoft released the Preview Update KB5086672 as an out-of-band update for Windows 11 24H2–25H2. It is intended to resolve the issues caused by the withdrawn Windows 11 Preview Update KB5079391. However, based on the information I have received and reader comments, the new update appears to have additional issues.
On March 26, 2026, Microsoft released the regular preview update KB5079391 for March 2026 for Windows 11 24H2–25H2. This update included a long list of fixes and improvements for various components (including a fix for the ERROR_BAD_PATHNAME update error). In addition, the AI Copilot components are being updated.
I reported in the blog post Windows 11 24H2 – 25H2: Preview Update KB5079391 (March 26, 2026) about the preview update. It also notes that these preview updates are always optional and are only offered via Windows Update on unmanaged systems.
As early as in the German blog post Windows 11 24H2 – 25H2: Preview Update KB5079391 (26. März. 2026) , there were reader comments about installation issues with the preview update KB5079391. And the update caused "collateral damage" for some readers. Just days after its release, there were reader comments on the German blog stating that this update was no longer available for Windows 11 24H2 and 25H2.
Microsoft had withdrawn this preview update and announced this in the "Known Issues" section of the support article KB5079391 with the following entry.
Rollout of this update is temporarily paused due to installation error 0x80073712
I mentioned this in the blog post Windows 11 24H2 – 25H2: Rollout of Update KB5079391 suspended. Microsoft intended to prepare and roll out a fix.
Out-of-Band Preview Update KB5086672
On March 31, 2026, Microsoft announced the out-of-band update KB5086672 on the Windows 11 24H2 and 25H2 update page and is rolling it out as an optional update via Windows Update and the Microsoft Update Catalog. This out-of-band update for Windows 11, versions 24H2–25H2, is cumulative and includes updates from previous security and non-security updates.
In the description, Microsoft states that the update includes a fix for an installation issue related to the preview update KB5079391 from March 26, 2026.
[Setup] Fixed: While installing the March 2026 Windows preview update (KB5079391), some devices running Windows 11, version 25H2 or 24H2, might encounter the following error:
Some update files are missing or have problems. We'll try to download the update again later. Error code: (0x80073712)
Issues with Update KB5086672
While Microsoft still states that no issues with the out-of-band update are known, blog reader Bolko points out reports of problems on the internet in this comment (thanks). He notes that the OOB update is not working properly and lists the following error symptoms. It includes a fix for an installation issue related to the March 26, 2026, Preview Update KB5079391.
At reddit.com is a thread Windows 11 KB5086672 rolls out after Microsoft pulls failed March 2026 optional update, which initially mentions the release of the special update. Regarding the "Network Nuker," it states there:
Installed it. And it promptly nuked my network controller. Had to uninstall the update and it fixed it.
Another user writes that the installation works via Windows Update:
Installs fine via Windows Update, but fails when installed via MSU update file, missing files, or corrupted files depending on PC.
But the installation from the MSU update package downloaded from the Microsoft Update Catalog fails again due to missing files or corrupted dependent files. "A waste of time, just like the Preview Update," Bolko notes. Is there anyone else among our readers who is having trouble with this update?
