DW 4 Unexpected Quit on Connection to Server

DW 4 is quitting on me when I try to connect to the server. I have been working
with these files and this server without problems until I started using
Contribute to update the site. Now DW quits when I try to connect to the server
directly from DW. I am working on Mac OSX, running DW4 in the classic
environment. Contribute is running on a Windows machine. Please help!!