Has KB5083769 / Apr 2026 Cumulative affected DISM offline patching?
Posted by Paul-P67@reddit | sysadmin | View on Reddit | 11 comments
Hi folks. I'm not sure if this belongs here or SCCM or elsewhere - please let me know if it needs moving/reposting.
Since updating to Apr 2026 / 26200.8246, I get the following error when trying to patch a cumulative MSU to an offline WIM or VHDX:
WARNING: Failed to add package WARNING: Add-WindowsPackage failed. Error code = 0x800401e3 Add-WindowsPackage: An error occurred applying the Unattend.xml file from the .msu package. For more information, review the log file.
I know about including the September 2024 (KB504308) file in the same folder, but even patching that file on its own fails.
The same WIM and VHDX and MSU files copied across to a device running the March 10th cumulative (26200.8037) can be patched successfully. I've also done this successfully months before.
I'll likely log this with MS through the feedback portal, but was wondering if anyone else has experienced the same issue?
Cheers. Paul.
Paul-P67@reddit (OP)
One last post in this.
I double checked and MoTW has no effect - it's just the use of DISM instead of Add-WindowsPackage that's required.
Thanks to everyone that chipped in. Good job u/Entegy !
Entegy@reddit
Hey this seems really weird but it appears that Add-WindowsPackage fails to apply this, but dism.exe /image:C:\mountdir /PackagePath:C:\PackagePath\KB5083769.msu worked. I'm currently waiting for my WIM to commit.
I have the checkpoint MSU in the same folder as KB5083769.msu file as well since I need it.
DeadlyBreakdown@reddit
This also worked for me. Thank you!
Paul-P67@reddit (OP)
You're right!
I had tried this (DISM instead of add-package) previously and had it fail, but since removing MoTW and retrying DISM at your prompting it's working!
So I guess it needs both? I'll re-test and double check tomorrow, but for now, it is patching and I am super grateful!
Thank you!
Entegy@reddit
Writing back to confirm that my process of adding language packs and Features on Demand, then applying KB5083769 with dism works. Just finished my end-to-end deployment test.
It's weird. Applying the CU to WinRE works with Add-WindowsPackage. It was the main Windows image that wasn't playing nice. Didn't even try WinPE, just switched it to using dism as well.
TheCrimsonCrusader-1@reddit
For accuracy for anyone new to DISM, it's actually:
dism.exe /image:C:\mountdir /Add-Package /PackagePath:C:\PackagePath\KB5083769.msu
I'm curious to what MS did to the April update to break the Add-WindowsPackage, but nothing surprises me anymore. They at least keep things entertaining at work!
AtlanticPirate@reddit
i guess it's a good thing this update isnt installing for you, its installation was leading to a bsod on my windows vm and very poor performance with explorer and browser processes, just uninstalled this update from both of my machines i use
NoSyllabub8790@reddit
prob not related, but we had an issue with some Shortcut files we would inject into our image. Turns out Windows gave them the MoTW and blocked them after the KB5083769 update. They worked fine before that for the last 6 months. Had to unblock the files for them to work. Might be related to the SAC changes they made in the KB?
Entegy@reddit
I wish it as that easy, but no. I removed Mark of the Web from the downloaded update files and they still won't apply to the image.
Paul-P67@reddit (OP)
Thank you both! At least I'm not the only one.
Regarding the MOTW, I did try with and without to no effect on the monthly. I can apply the dotnet update with no issues regardless of MOTW or which build I'm on.
Time to wait for MS I guess. Thank you!
Entegy@reddit
Yes, I can't apply this patch to an offline Windows 11 25H2 image. The image is straight from the ISO too, so it's clean.
It doesn't work with or without the checkpoint MSU. I need the checkpoint since I'm applying language packs and FOD. But I've tried without applying LPs/FoD either.
Not sure what's going on with the update because as you note, it applies just fine to online systems.