I agree this would be useful.
I too use many versions.
The files themselves do know which version they were created with - even down to the actual build (hotfix) number.
I think the problem is that the actual Archicad program is just called "Archicad.exe" (on Windows system anyway) no matter what version it is for.
So the operating system simply assumes the last installed version is the one to open with - unless you assign a different one as the default program.
Barry.
One of the forum moderators.
Versions 6.5 to 27
Dell XPS- i7-6700 @ 3.4Ghz, 16GB ram, GeForce GTX 960 (2GB), Windows 10
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