RS3 installation question

We have a multiple authors and have recently installed RH6 in our test environment -- RH workstation and RH6 server with a separate SQL reporting database. RH was working fine. Just recently we installed RS3 on the same server as RH6 -- utilizing a separate SQL db server. Since the install we are receiving an error when publishing from the RH workstation to the server, “Warning: Failed to publish to "robo6 test". reason: Cannot logon to server: vcnbtcsp02, Server does not support any type of authentication method..”
Has anyone encountered a similar problem installing RS3 on the same server as RH6? I heard the two are generally installed on separate machines, so my next step is to try that configuration. Thanks in advance for any pointers!