Unexpected challenge(HTTP status code=407) received while accessing HTTP proxy '%1' retrieving URI '%2'. This behavior differs from the behavior recorded during test creation. For authentication to playback correctly a challenge must be recorded during test creation.
When the test was recorded, no basic authentication was required on the proxy server. When the test is run, the proxy server is requesting basic authentication information that is not in the test.
Record the test again to capture basic authentication information. Play back the new test, or add the basic authentication information to the request in the original test.