A common situation is that SeqZap is running automated tests on the command line by being invoked by a build system slave (for example Jenkins) running as another user than the primary user account on a machine.
COM and DCOM also brings an authentication and permission system which is different from normal permission systems, at least, when it comes to error messages.
To help debug these issues the OPCToolTester.exe file shipped with SeqZap in the ZapTools\OCP_DOTNET451 folder. This program will connect to the local OPC server and list all servers and fields found using the local OPC server and writes them on the console (standard output), this makes it suitable for running as the SERVICE user where SeqZap Studio cannot run due to user interface limitations.
The following section documents the arguments that the OPCToolTester.exe can take.