Update:
Although I will perform some more tests to be sure; I think I solved the problem.
For gsak.exe and gpsbabel.exe I opened their properties and ticked the box "run as administrator".
The drawback is that each time I start GSAK I need to confirm that I allow it to run as administrator, but it works. Image may be NSFW.
Clik here to view.
I feel that this is a 'workaround' rather than a solution so if anybody still knows the proper solution the please let me know.
Although I will perform some more tests to be sure; I think I solved the problem.
For gsak.exe and gpsbabel.exe I opened their properties and ticked the box "run as administrator".
The drawback is that each time I start GSAK I need to confirm that I allow it to run as administrator, but it works. Image may be NSFW.
Clik here to view.

I feel that this is a 'workaround' rather than a solution so if anybody still knows the proper solution the please let me know.