I managed to run Open Office from my normal account, but I wonder how this was made possible. It was impossible to run Open Office, even by clicking on "run as administrator". Someone gave me the link to
this forum and how to disable UAC. That didn't help. I then became a member of this forum and started this topic. A few minutes ago I decided to bring everything back to "normal" and enabled UAC again. And guess what? Now I can open Office without a problem. When I recapitulate the only thing that changed in my account was disabling an re-enabling UAC again. Now I have also the missing maps in my useraccount as described higher. Can someone explain me how this is possible? What really happens when disabling and re-enabling UAC? Thanks to all those who tried to help me.

I'm not sure how just disabling and enabling UAC would fix that.
From what I know that is what happens when you disable it and enable it. It gets disabled and enabled again. Nothing that fixes things.