I thought it might be AV that is doing it, I have ESET Internet Security, so I added the whole GRAPHISOFT folder to exception list within HIPS and Real-time protection. Nothing worked, still the same.
When you are adding exclusions to your antivirus, as well as the main program folder, don't forget to add the Graphisoft folder in your user profile.
Also in your user folder are some hidden folders in AppData/Local and AppData/Roaming - you will have to show hidden files/folders to see these.
They contain file that Archicad is accessing all of the time - so add them to your exception list as well.
Also check whether Windows Defender has been disabled - not needed if you have your own AV.
I think it should be off by default when you install another AV.
One of the forum moderators.
Versions 6.5 to 25
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