I have been using Mp3tag successfully for a few years.
Now I have encountered this problem. When I click on Help/Contents I do not get the Help page, but instead another program opens. This is Notepad++, a text editor I also use.
The same thing happens when I press F1.
I have tried downloading the latest versions of both Mp3tag and Notepad++, but the problem remains.
If I disable Notepad++ the problem disappears. Otherwise the only way I can get Help is via the Mp3tag website.
It seems there is some conflict between Mp3tag and Notepad++. Any ideas?