Are you still using version 3.21 of RailPro Assistant? If so you'll need to update to version 4.01. RPA and the file server had a makeover between the versions. The ports used by RPA changed and the username & password is no longer required. I don't believe that RPA 3.21 is supported by the new server any more (I haven't personally checked though), only 4.01.
If your still using 3.21 and upgrading to 4.01 doesn't work (or if you are using 4.01 already) let us know and we can look further into it.
- Tim