UrgencyCritical · 1 exploited
RiskModerate · 1 mitigated
Resolved
Windows release health · Windows 11, version 26H1 and 5 more versions
Host folder shares might be unavailable in Hyper-V-based Linux VMs
Plan9 host folder shares might not appear in the guest environment after installing the September 2026 security update.
What to do
Resolved by KB5129194. Install it, or any later update for your Windows version, on affected devices.
Fixed by KB5129194 Published 14 Sep 2026 · OS build 28000.29566Days from the update that caused it to the fix
0/6Windows versions where it is open
14 SepLast updated by Microsoft · 30d ago
3Other issues from KB5124012Status on each Windows version
Microsoft can list one issue differently per version| Windows version | Status | Caused by | Fixed by | Updated |
|---|---|---|---|---|
| Windows 11, version 26H1Home and Pro · Enterprise and Education | Resolved | KB5124012 · 8 Sep | KB5129194 | 14 Sep |
| Windows 11, version 25H2Home and Pro · Enterprise and Education | Resolved | KB5124008 · 8 Sep | KB5129195 | 14 Sep |
| Windows 11, version 24H2Enterprise and Education · LTSC | Resolved | KB5124008 · 8 Sep | KB5129195 | 14 Sep |
| Windows 11, version 23H2Enterprise and Education | Resolved | KB5122880 · 8 Sep | KB5129242 | 14 Sep |
| Windows 10, version 22H2 | Resolved | KB5122878 · 8 Sep | KB5129236 | 14 Sep |
| Windows 10, version 21H22021 () LTSC | Resolved | KB5122878 · 8 Sep | KB5129236 | 14 Sep |
The update that caused it
Other issues from KB5124012
KB5124012- USB audio devices might fail to start or produce no soundMitigated · updated 13 Oct
- Domain-joined devices might lose their secure trust relationship with the domainResolved · updated 8 Oct
- Remote Desktop Services might stop responding after Sept. 2026 security updateResolved · updated 17 Sep
What changed
First observed 14 Oct 2026No field changes in the recorded history.
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