How to use the DISM to repair Win8.1 system images

The DISM tool is a deployment image service and management tool, an upgraded version of the Windows Update Cleanup Tool, and can also repair corrupted Windows images. How does Win10 come with the DISM tool to fix Windows images?

When Windows image is not available, you can use the tool Deployment Image Servicing and Management (DISM) to update the file and correct the problem. You can use DISM to repair an offline Windows image in a WIM or VHD file, or an online Windows image. Online Windows images also try to fix them when they are not available. The fix for this operation is the same as the "required feature" used by the same source, and this source is determined by the Group Policy settings (for more information, see Configuring Windows Repair Sources). When using the DISM tool to repair an online or offline image, you can use the /Source parameter with the /RestoreHealth parameter to specify additional fix source locations to search for the files you need.

DISM's /ScanHealth, /CheckHealth, and /RestoreHealth parameters are only available when serving Windows(R) 8 or Windows Server® 2012 images.

Check if the image is repairable

1. Scan the image to check for corruption. This operation will take a few minutes. For example, type the following at a command prompt:

Dism /Online /Cleanup-Image /ScanHealth

2. Check the image to see if any corruption is detected. For example, at the command prompt type:

Dism /Online /Cleanup-Image /CheckHealth

When using the /CheckHealth parameter, the DISM tool will report that the image is in good condition, repairable, or Not repairable. If the image is not repairable, you must discard the image and start over. If the image can be fixed, you can use the /RestoreHealth parameter to fix the image.

Repair Image

1. Use the /RestoreHealth parameter to fix the image. For example, to repair an offline image using the mounted image as a repair source, type the following at a command prompt:

Dism /Image:C:\\offline /Cleanup-Image /RestoreHealth /Source:c:\\test\\mount\\windows

Or, to use some of your own sources and not use Windows Update to fix an online image, type:

Dism /Online /Cleanup-Image /RestoreHealth /Source:c:\\test\\mount\\windows/LimitAccess

If /Source is not specified for the repair file, the default location of the required function will be used (for details) , see Configuring Windows Repair Sources). If more than /Source is specified, the files found in the first location will be copied and files in other locations will be ignored. You can use /LimitAccess to prevent the DISM tool from using Windows Update as a repair source or backup repair source for online images.

For the DISM tool, the system home introduced: "Use DISM, easily delete the win8.1WinSxS redundancy update" "Quickly know WinSxS folder size in Win8.1 has a trick." You can refer to the reference and use this tool.