#310 - How to troubleshoot a WinCC Unified connection to PLC

 - After downloading the HMI project to WinCC (setting it to Start runtime) from TIA Portal, check the running status on SIMATIC Runtime Manager.

- In case of PLC not reachable error, check the HMI connection in TIA Portal and the access point (i.e., S7ONLINE).

- From control panel, open the Communication Settings (Siemens), this is the equivalent to the old PG/PC interface. Check the NIC configured for the S7ONLINE access point.

Example in simulation environment (for PLCSIM online access):

Note: for PLCSIM advanced configured as TCP/IP Single Adapter online access, set the S7ONLINE as PLCSIM Virtual Ethernet Adapter.TCPIP.1 (same path as the one used to go online into PLC).

Example in production environment:

- Other checks are to test-netconnection between machines over OPCUA port, check certificate dates, check date and times.