Back to top Share via Share via... Twitter LinkedIn Facebook WhatsAppSend via e-MailPrintPermalink × “pniopcac.exe Assertion" Error while establishing a connection This error is seen on PCs with Siemens PLC programs installed. The cause of the error is trying to apply the Siemens Profinet protocol to the Simplinx Network Adapter. Solution: View Network Adapters Double click the Simplinx Adapter to open its properties Remove “PROFINET IO RT-Protocol VX.X” protocol Save and exit