Missing context Menu on (some) Windows 7 machines


I have installed the Nextcloud desktop client on a few machines already and while it worked quite well on every Windows 10 machine, most of the Windows 7 clients just refuse to add the context menu even after reintalling a couple of times. I already rebooted the machines and tried to run the batch file that should add the context menu.
Unfourtanetly the batch files just can’t get executed on the windows 7 machines saying that either a module is missing or the path is wrong (which is not I already checked that a 100 times).
Basically I did everything the first 2 pages of Google told me to do and I still can’t get it to work.
All of the machines on which the context menu is not shown there is dropbox installed so the sync icons are not there anyway (but syncing works). Maybe that has something to do with it ?

I would really appreciate any help to solve this issue as it is not really an option to reinstall every machine.