Have you verified that you have selected the correct property on the Web Adapter (see screenshot). When you say it is unable to open the sight what is happening? Is IE coming up? Is an error being thrown? Would it be possible for you to attach verbose studio logs to this SR? You can enable studio logs under: Tools -> Options -> Pega Robotics -> Studio Diagnostics. You will want to turn File Publisher Mode to On and you will want to set Log Categories to Verbose.