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With GeoGebra 6 Classic installed, double clicking a ggb file does not open the file in the app. The app is started, but the file is not loaded.
I guess there woeld be no point in me creating my own association for ggb files to C:\Users\username\AppData\Local\GeoGebra_6\app-6.0.620\geogebra.exe, since there may be a new version coming at any moment messing up the file location of geogebra.exe.
Frankly, what we need is a shortcut in C:\Users\spaternotte\AppData\Local\GeoGebra_6\ pointing to the latest geogebra.exe. THIS shortcut can be used to for the file association, instead of the one that is now placed at the desktop, which is pointing to the executable update.exe.
The same question 
Meanwhile I figured out an interim solution.I had the GeoGebra 6 Classic installer installed. I removed this and replaced it with the GeoGebra 6 Classic MSI, which by the way is very hard to find. After using the MSI-installer, GeoGebra is properly installed in C:\Program Files (x86)\ and provides proper file association, so double clicking a ggb does open the file in GeoGebra.
The only thing is now, that i have to keep track of possible updates and install these manually.
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