I have modeled a structure made of outer and inner cables as well as membranes, and get a message about instability or the error message "Jacobi matrix is not positive definite" in the RF‑FORM‑FINDING add-on module. What should I do?
When entering the geometry of a ribbed timber plate, I always get error message No. 30343: "The computed stiffness matrix is not positive definite". How can I define the surface?
I have downloaded installation packages from the Dlubal website. When trying to install them, I get a warning message from my security software that the installation packages contain malware. Is that really the case?