As a PC user, your pre-downloaded Windows 11/10 ISO image tends to get outdated due to Microsoft releasing cumulative updates monthly for the OS. Consequently, the computer then needs to download the latest updates manually each time you reinstall the OS. In this post, we show you how to add Windows Update Packages to Windows 11/10 ISO Image.

This can be done using a process called Slipstreaming. The slipstream process injects new updates to your downloaded Windows ISO image file – this way, you won’t need to download a complete image each time a new update is released.

Add Windows Update Packages to Windows 11/10 ISO Image

We can add Windows Update Packages to Windows ISO Image in 3 ways. We’ll explore this topic under the methods outlined below in this section as follows.

1] Using DISM GUI tool

To add Windows Update Packages to Windows ISO Image using DISM GUI tool, do the following:

Mount your Windows ISO to a drive letter. For the purposes of this tutorial, we assume the Windows 10 version is 21H1.
Create a folder, example D:\Win10ISOand copy the contents of the ISO to the folder.
Next, visit the Microsoft Update Catalog and get the Windows Update .msu or .cab packages.
Depending on your OS architecture, search Microsoft Update Catalog using the phrase windows 10 version 21H1 x64 to find updates available for Windows 10 v21H1 64-bit. If you’re running 32-bit Windows, then use the x86 keyword instead of x64.
Create a for example; D:\v21H1 Updatesand download all the available updates to the folder.

Alternatively, you may use a third-party tool called WSUS Offline Updater to download the MSU packages pertaining to your computer.

Next, download the DISM GUI tool and run the program as administrator.
Next, create a folder, for example D:\Mounted-WIM where you’re going to mount the install.wim file
In the DISM GUI tool, point the path to install.wim. In this example, the path would be D:\Win10ISO\sources\install.wim.

Note: In the sources folder, if the file install.esd exists instead of install.wim, you’ll need to convert the ESD file to WIM format in order to service the image.

Next, click the Display WIM Info button to view the indexes in the WIM file. For the purposes of this tutorial, we’ll choose Index: 6 for Windows 10 Pro.
Next, select 6 in the Index drop-down box
Next, in the Mount location, type in D:\Mounted-WIM.
Click the Mount WIM button.
Click on the Package Management tab in DISM GUI.
Type in or browse to locate the packages folder. In this example, the Windows Update packages are stored under D:\v21H1 Updates.
Click on the Add Packages button.
Go back to the Mount Control tab, and click Dismount WIM.
Click Yes when you’re asked to commit changes made to the WIM. Now, every available Windows Update package (*.msu and *.cab) in that folder will be integrated into the install.wim image.
You can now delete the D:\Mounted-WIM and D:\v21H1 Updates folders manually.

You’ve now successfully updated your Windows Setup source or USB installation media. You can run Setup.exe now if you plan to do a Windows 10 repair installation or in-place upgrade of Windows 10. Or, you can point to the path of the updated install.wim if you want to run DISM mentioning the setup source path to fix any corruption in the system.

2] Using DISM console tool

To add Windows Update Packages to Windows ISO Image using DISM console tool, do the following:

Press Windows key + R to invoke the Run dialog.
In the Run dialog box, type cmd and then press CTRL + SHIFT + ENTER to open Command Prompt in admin/elevated mode.
In the command prompt window, type the command below and hit Enter to get the WIM file info and its indexes.

dism.exe /Get-WimInfo /wimFile:"D:\Win10ISO\sources\install.wim"

Next, to mount the install.wim image (index: 6) to the specified folder, run the command below:

dism.exe /Mount-WIM /WimFile:"D:\Win10ISO\sources\install.wim" /index:6 /MountDir:"D:\Mounted-WIM"

Next, to add Windows Update Packages to the mounted WIM file, run the command below:

dism.exe /image:"D:\Mounted-WIM" /Add-Package /PackagePath:"D:\v21H1 updates"

To verify that the packages appear correctly, run the command below:

Dism /Get-Packages /image:<path_to_image>

After reviewing done updating your image, you can now proceed to unmount the WIM file.

To unmount the WIM file and to apply the changes (package addition or removal), run the command below:

dism.exe /Unmount-wim /mountdir:"D:\Mounted-WIM" /commit

Exit CMD prompt.

3] Using NTLite

To add Windows Update Packages to Windows 11/10 ISO Image using NTLite, do the following:

Mount the Windows ISO.

Alternatively, if you have the Windows installation USB media (instead of ISO) and want to update it, insert the USB drive instead.

Create a folder, e.g., D:\W10-20H1-Setup and copy the contents of the mounted drive to the folder.
Next, download NTLite and install it.
Launch the program.
In the NTLite window, click Add > Image directory.
Next, select the folder that contains the install.wim image you want to customize – e.g., D:\W10-20H1-Setup\Sources.

Note: If the ISO/USB setup disk/mounted folder contains install.esd instead of install.wim, you’ll need to first convert the ESD file into WIM in order to service it.

Next, select the edition of Windows 10 you want to slipstream. The Windows 11/10 ISO, downloaded from Microsoft, contains several Windows 10 editions in it.
Right-click on the chosen edition and click Load.
Click the Updates tab on the left.
Click on the Add button and select Latest online updates.
Next, select all the available updates from the list and click Enqueue. The Windows Update .msu files are now added to the update queue.

Unlike the other methods, you don’t need to manually download the .msu packages from the Microsoft Update Catalog.

Once you add the updates to the update queue, click on the Apply button.
Finally, click on the Process button to complete the integration process. NTLite will prompt you to disable the real-time antivirus protection to speed up the file copy process.
When done, exit NTLite program.

That’s it on the 3 methods to add Windows Update Packages to Windows 11/10 ISO Image!