Unable to connect to the remote server
No connection could be made because the target machine actively refused it 127.0.0.1:8090
If the service is defined in the current solution, try building the solution and adding the service reference again.
This exception (and a number of others) can be quite misleading - you will sometimes get this exception if the connection is refused but you may also see it for reasons that have nothing whatsoever to do with the error that is ostensibly being reported.
You need to turn on the tracing options in your WCF configuration editor (both client and server, as applicable), reproduce the exception with the tracing options turned on, then review the trace log that has been generated.
http://msdn.microsoft.com/en-us/library/ms733025(v=vs.110).aspx[
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