That 'can not read plan' message can mean that you are trying to open a newer version file (say 23) in an older version (say 22).
If you open through the FILE menu in Archicad, the open dialogue box will show you the file version when you select it.
Barry.
One of the forum moderators.
Versions 6.5 to 27
i7-10700 @ 2.9Ghz, 32GB ram, GeForce RTX 2060 (6GB), Windows 10
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