Answer:
The file for the cross-section library is called ProfileDB.ADB. By default, it is located in the folder
"C:\Program Files\Dlubal\RFEM 5.xx" or "C:\Program Files\Dlubal\RSTAB 8.xx."
If the file is damaged or blocked (for example, by a virus scanner), the error shown in the image is displayed. In this case, we recommend adjusting the virus scanner's filter settings.
As an alternative, you can perform a new installation. You will be asked if you want to uninstall the program first. Confirm this query, then reinstall the program with administrator rights and, if necessary, a temporarily deactivated virus scanner.
In rare cases, the cause may be missing Windows updates. Therefore, search for the updates of the operating system and install them.