BadSecurityChecksFailed error - by: Mirhaj

Hi,

I am implementing OPC UA clientin C# (with .Net framework 4.7.2) using Quick OPC sdk (EasyUA client). When trying to connect to a Siemence OpcUa server, it throws this exception: OPC UA service result - {BadSecurityChecksFailed}. An error occurred verifying security. --> {BadSecurityChecksFailed}. Certificate chain not complete.

I have set in the code for now to AccepAnyCertificate = true. I have also set HttpsCerticateAcceptancePolicy.AcceptAnyCertificate = true. Since I am connecting to the server which is availabe on internet I thought https certificates should be accepted. Worth mentioning that the server is Sign&Encrypt, Basic256Sha256 Seimence server.

Meanwhile I can connect with UaExpert to the server and verify the server but throws the exception when trying to connect with my C# client.

Could you help me on what I should do now?

I also found out some other people had the same exception in Online Forums but their application was different than mine, so I couldn't find the solution.

Best,
Ahmad