Wcf service only works localhost

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WCFServices

I have developed a simple WCF service and an application to consume the service. Both Visual Studio and IIS are on the same (developers) machine.

-Application is compiled and works fine
-The application is then published and browser automatically displays the URL
http://MyServerName/Math/publish.htm. Application works fine

BUT

when I tried to use a remote client, the application errors with "there was no end point listening at http://localhost:49380/ServiceName.svc"

Why is it trying to use the localhost:49380 URL (default by VS)?

Visual Studio contains the app.config which is configured that specifies the endpoint like this:
endpoint address="http://localhost:49380/MathService.svc" binding="basicHttpBinding"
.....
Tried to edit the endpoint here but then not even the local browser would work.
Any ideas?

What I have tried:

I tried to modify the app.conf with the URL that works in localiy
I also try to specified the same URL with and without port

http://MyServerName:port/Math/publish.htm