To update Windows in the OS template: 

  1. Connect to the server that runs Windows with the Admin permissions. 
  2. Download the OS image from the ISPsystem repository. 
  3. Extract the files to C:\win_update\win_template. 
  4. Download updates from the official website and locate them to C:\win_update\updates. 

  5. Open powershell and enter the commands one by one: 

    mkdir c:\win_update\wim

cd c:\win_update

DISM /Mount-Wim /WimFile:win_template\win2019\sources\install.wim /index:2 /Mountdir:wim

DISM /image:wim /Add-Package /Packagepath:updates

DISM /Unmount-Wim /Mountdir:wim /commit
    CODE
  6. Zip the updated file C:\win_template\win2019\sources\install.wim into the archive with the OS image.
  7. Add the OS image into the storage and check its installation on the server.