W11 25H2 26200.7922 (or earlier) / Cannot login to network shares after update

I just wanted to document this problem because we had many Windows 11 25H2 computers suddenly experience problems after installing Windows 11 25H2 26200.7922 update. Prior to installing this update (possibly previous updates as well) they could no longer log in to the network shares. These networks/computers are peer networks, local user accounts, and basic setups. There has been no network sharing issues until this update (or updates) installed.

We found the following and corrected the network sharing login problem where they can access the network shares again:

Microsoft Q&A: how to get group policy for duplicate sid

echo Run powershell as Administrator echo This compliments the duplicate SID failure on the computer accessing the host New-Item -Path HKLM:\SYSTEM\CurrentControlSet\Policies\Microsoft New-Item -Path HKLM:\SYSTEM\CurrentControlSet\Policies\Microsoft\FeatureManagement New-Item -Path HKLM:\SYSTEM\CurrentControlSet\Policies\Microsoft\FeatureManagement\Overrides Set-ItemProperty -Path "HKLM:\SYSTEM\CurrentControlSet\Policies\Microsoft\FeatureManagement\Overrides" -Name "1517186191" -Type 'DWord' -Value 0 -Confirm:$false

I have added a link to your solution in a post of mine in TenForums.
A consolidated network setup checklist for Windows 10 and 11 - my post #4 - TenForums


Denis

Keep in mind that this override is temporary and will eventually stop working. Unique SIDs are the long-term answer.

Nipdawg said:

I just wanted to document this problem because we had many Windows 11 25H2 computers suddenly experience problems after installing Windows 11 25H2 26200.7922 update. Prior to installing this update (possibly previous updates as well) they could no longer log in to the network shares. These networks/computers are peer networks, local user accounts, and basic setups. There has been no network sharing issues until this update (or updates) installed.

Click to expand...

The network restriction on duplicate SID's was rolled out in the August 2025 updates for 24H2 & 25H2.

A key takeaway is imaging of a new system by restoring a full image backup (cloning), or by installing a sysprepped image which hasn't been generalized, is no longer acceptable if you intend to use file sharing and remote desktop. While you can use the temporary GPO to override the restriction, a better solution is to eventually change the local PC's SID using a tool like SIDCHG.

SIDCHG SID Change Utility

garlin said:

a better solution is to eventually change the local PC's SID using a tool like SIDCHG.

SIDCHG SID Change Utility

Click to expand...

But do note that even a single licence for non-commercial use costs over £100.


Denis

cant you just create a new user, migrate user data, delete old user

to change sid?

BobOmb said:

cant you just create a new user, migrate user data, delete old user

to change sid?

Click to expand...

If you look at your own user account SIDs in
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList
you'll see a long string
that is set by Windows for each computer and it's the clash of those strings between network computers that is the problem.


All the best,
Denis

BobOmb said:

cant you just create a new user, migrate user data, delete old user

to change sid?

Click to expand...

No, the root problem is the system's SID. Regardless of which users exist on the system, Windows now checks for duplicate system SID's when making network sharing requests. When you use a SID change tool, it will "fix" all the users' personal SID's at the same time since they're derived from the system SID.

Try3 said:

But do note that even a single licence for non-commercial use costs over £100.

Click to expand...

You can use the trial key. How often are you needing to fix the SID, once you've learned the lesson?

There's nothing wrong with restoring another PC's image to a different PC. What's wrong is leaving both systems running and expecting file sharing and remote desktop to work between them. If you migrate a backup to a new PC, get rid of the old PC (or change the SID on one of them).

If you're sysprepping (and forgot to generalize an image), shame on you.

If you're using Macrium (or another backup app) for cloning PC's, the software vendor needs to do a better job of highlighting this concern. I mean Macrium should add a native SID change feature, and just charge you extra for the option.

I mean Macrium should add a native SID change feature, and just charge you extra for the option.

Click to expand...

I've wondered which backup programs offer this, but I didn't wonder enough to ask.