If you enabled the option "Only allow secure PG/PC and HMI communication" in the TIA project, the certificate must to be extracted for later use.
- Select "Device configuration" for the PLC added
- Navigate to "General" -> "Protection & Security" -> "Certificate manager" -> "Certificate management with TIA Portal"
- Right-click the device certificate of the PLC and select "Export certificate"
- Save it on disk
The path to this file must be passed to the sld later on with the option "--certificate".
Alternatively, the certificate can be retrieved afterwards directly from the PLC by using the SIMATIC AX Certificate Management tool.