This DCOM error will appear when it succeeds in launching an OPC Server or OpcEnum, but fails to receive a reply from either of the applications. This error could be caused under several conditions:
There are cases where an OPC client application can launch a remote OPC Server, but is unable to receive further responses. Thus, DCOM will inform the OPC Client that the launch of the remote server was successful, but the OPC Client will be unable to continue communicating with the OPC Server application. In this case, the OPC Client application will display DCOM Error 0x80070005. In essence, this error occurs when DCOM communication is stopped by the Access Control List (ACL) of either the OPC Client PC or OPC Server PC.
If you receive DCOM Error 0x80070005, check if the OPC Server application is actually running on the OPC Server PC. If you received this error when you tried to browse for OPC Servers on the OPC Server PC, check if OpcEnum is running. If either is running, end both processes on the OPC Server PC. Then try to establish communication again. If you still receive the same DCOM Error 0x80070005, then the cause is as listed above. If you receive a different DCOM error, then you will need to search for that specific error instead.