Did it use to work or was it always like that?
error 5: access is denied.
I don't know why the program isn't allowed to write to the documents folder, but that's indeed a big problem. Maybe the permissions of the document folder are not well set and you need to fix them? To do that, you have to right click the document folder and select "Properties". Then in the "Security" tab you look if your username is allowed to write.
If we don't find a fix to your problem, the last recourse is to use the portable version of the program. As you can run it from any folder, you just have to place it in a folder where you are allowed to write.
Please keep me informed how it goes.