The BIM Server is an earlier version (called "build") than ArchiCAD.
BIM Server is the server when doing Teamwork projects, ArchiCAD is the client.
You should run the latest hotfix and update both ArchiCAD and the BIM Server.
It might be that ArchiCAD is actually on the latest build so you will not be able to update that. Run the update and see if you ca nstill update the BIM Server to the same build.
If this is not possible, you may have to uninstall both, then reinstall both, then apply the latest hotfix to both.
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