DISM lacking Package Manager commands (Cleanup-image)

Hello everyone,

I seem to have some serious problems with my Windows 10 Build 10.0.10586.113. These started after trying to take Ownership of C:/ (where I installed Windows). I tried this because on several occasions trying to move/copy files in different directories I could not do it (ownership problems seem to be not unusual after upgrading from Win 8). When trying to take ownership of C:/ and all its subdirectories I got several error messages ("Acess denied"). At first I just skipped them, but there where so many my finger just got tired (and it also seemed that something was going wrong). I downloaded a .reg which adds the option "Take Ownership" when right-clicking on a folder. Using this added my user account (with administrator rights) to the security options for the folders but the checkboxes were all empty. However I now could restart the procedure I tried before and this time there were no "Acess denied" errors and afterwards all checkboxes were filled with full acess (and all other options).

For a couple of days all seemed to work fine.

Yesterday I tried to open an *.jpg file and the usual W10 app would not be able to open it anymore. Same when trying to open a pdf using edge. So something was wrong with the apps. All the apps (like calculator, store etc.) just immediately crash. Of course I tried several troubleshootings for this known problem. Nothing worked.

Now I'm trying to repair my system using DISM or an inplace-upgrade.

After spending the last two days trying to fix these problems, I'm kindly asking for your help.

1) I cannot run any of the DISM commands required to repair my Windows build like e.g.
Dism /Online /Cleanup-Image /RestoreHealth
Dism /Online /Cleanup-Image /RestoreHealth /Source:wim:C:\sources\install.wim:1 /limitaccess (using the install.wim from the latest .iso and for esd the latest build from Media Center respectively)
Same with ScanHealth etc.

I am getting Error 87: cleanup-image unknown
Dism /Online /? lacks the Package Manager commands like Cleanup-Image


2) After running SCF /Scannow the first time it said: no corrupted files. Immediately starting Dism /Online /Cleanup-Image /ScanHealth works and reports no problems.
Opening a new cmd and restarting Dism /Online /Cleanup-Image /ScanHealth gives Error 87: cleanup-image unknown again

3)Trying to do an inplace upgrade with the latest .iso as well as with the Media Center gives me an error during initializing the setup (at 25%); A problem occured. I can just click "OK" here and it stops.

4) Mounted an offline image with dism /offline and used the dism folder of this mounted build to replace it with my own Dism folder in System32 (maybe stupid, but I thought it could repair any corrupted Dism files)

5) If I now run SCF /Scannow "some corrupted files could not be repaired"
Log file attached.

Please help me to get either Dism /online /Cleanup-Image or the inplace upgrade running!
As I use a Windows build with German language I tried to translate the error messages. If something sounds weird just ask.
I cannot attach the DISM.log. It's over 9 MB...

Thank you for your kind help.