Answer:
You have installed an outdated version of RFEM 6 or RSTAB 9, where the Concrete Foundations add-on was not available. Install the latest version of RFEM or RSTAB. You can download them in the Dlubal Center.
Add-on Concrete Foundations
I cannot activate the Concrete Foundations add-on. Why?
Author
Mr. Faulstich is responsible for the quality assurance of the RFEM program and provides customer support.
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