If you want to mount a WIM-image with ImageX, you can mount it with read-only access or with write-access.
To mount a WIM-image with read-only access, type:
imagex /mount %path_to_wim_folder%\%filename%.wim 1 %path_to_destination_folder%
imagex /mount C:\wimfiles\win7.wim 1 C:\mounted_images
Should you decide to modify the mounted directory (like adding files to C:\mounted_images), and then commit the WIM-file, the following error appears:
ImageX Tool for Windows
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Unmount Error: Changes to the Image could not be commited.
An attempt was made to commit an image that was mounted for read only access.
This is not valid. To commit an image, mount it without the read only flag
This error occurs because you have mounted the image with read-only access. To mount an image with write-access, you should use the following command:
imagex /mountrw %path_to_wim_folder%\%filename%.wim 1 %path_to_destination_folder%
imagex /mountrw C:\wimfiles\win7.wim 1 C:\mounted_images
Then, after you have made some modifications, enter the commit command to write back the changes to the WIM file:
imagex /commit C:\mounted_images