Steve Endow tackles the econnect error where There was no endpoint listening at at http://server:48620/Dynamics/GPService
Dynamics GP Land: GP 2010 Web Services error: There was no endpoint listening at at http://server:48620/Dynamics/GPService
Install, Upgrade & AdminDevelopment & IntegrationGP 2010
Archived post from 2012. Dynamics GP and the links it points to have changed since; check current documentation before relying on version-specific steps.