When making an OPC DA connection from a client node to the server using DCOM. The server node only allows one connection. Is there a way to change this?
What OPC Server are you talking about? Some OPC Servers only allow single connections due to licensing or technical limitations.
It is a CoDeSys OPC server
I am not personally familiar with this server. Your question is probably best answered by someone at CODESYS. Maybe Gabriel Michaud-Verreault has some more experience with this server.
OK thanks for your help anyways
Sounds like a license limit. You could confirm that by reviewing your OPC Server logs. From the client side (interface / opc client), only an access denied will be returned, so you should get in touch with the folks at CODESYS.
Each license can be different, but I have not seen their opc server enforce a connection limit before, but better to confirm with them.
When you are testing it, are you opening both client instances using the same user account? There may also be other things going on. Are you getting a specific error code when you try to establish a connection (review the messages logged on both the client and the server)?
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