Windows 10 dism unmount offline image failed with error 32

Question

Hi there

I am trying to change some registry keys in an offline image BOOT.WIM as to ensure a recovery-media startup uses the right screen resolution.

Therefore i use Windows Powershell (admin) and make some commandline entries.

dism /mount-wim /wimfile:G:\SOURCES\BOOT.WIM /index:1 /mountDir:H:\Scherpbierje\export

reg load hklm\temp "H:\Scherpbierje\export\Windows\System32\config\DEFAULT"

reg add "HKLM\temp\Software\Microsoft\Windows NT\CurrentVersion\AppCompatFlags\Layers" /t REG_SZ /v "X:\Programs\Paragon Software\program\hdm17.exe" /d "HIGHDPIAWARE" /f

reg add "HKLM\temp\Control Panel\Desktop" /t REG_DWORD /v LogPixels /d 96 /f

reg add "HKLM\temp\Control Panel\Desktop" /v Win8DpiScaling /t REG_DWORD /d 0x00000001 /f

reg add "HKLM\temp\Control Panel\Desktop" /v DpiScalingVer /t REG_DWORD /d 0x00001018 /f

dism /unmount-wim /mountDir:H:\Scherpbierje\export /commit

However by the unmount-action will not work, I get error 32 : the proces has no acces to the file while it is used by another proces

The BOOT.WIM will not be saved including the alterations I have made.