DISM!!

It is used to repair the health of Pc/ laptop when sfc scan fails to do so. It also tries to repair the corrupted dll files that are found in system file checker scan. The method to perform it is quite easy. It is necessary to use sometimes, because if many files are corrupted windows start misbehaving for example, it does not shut down properly and does not give appropriate response of our commands.

METHOD:

TO CHECK IF AN IMAGE IS REPAIRABLE:
1. Press Ctrl + X and select command prompt admin.

2. Then type the following command. 
                    Dism /Online /Cleanup-Image /ScanHealth

3. And then type this command.
                    Dism /Online /Cleanup-Image / CheckHealth

Now this will tell you whether the image is repairable or not, if it is repairable then we will try to restore the health. To restore health try the following commands
a. For offline image use the following command
            Dism /Image:C:\offline /Cleanup-Image /RestoreHealth /Source:c:\test\mount\windows

b, For online image restore use the following command
         Dism /Online /Cleanup-Image /RestoreHealth /Source:c:\test\mount\windows /LimitAccess

Hope these methods will be sufficient to restore the health of your pc.