Problem

After installing and configuring the B2Bi Client, when trying to connect, getting the above error.

Resolution

The configuration was wrongly done (there should be no references to Passport). The correct steps are to use the configure tool, specify the hostname and port number of Integrator, and then, when running TSClient.exe, select "Native B2Bi authentication" and fill in the username and password that you use to connect to the B2Bi server UI. (In that UI itself, you can also create other user accounts to use with the client.)