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What are the recommended client-side proxy server settings?


You are not able to connect to the Avalara production web service, even though the same .NET code worked in development. Receiving "Unable to connect to the remote server."




  • The AvaTax web service provides our subscribers with a standard SSL (secure socket layer) access point that makes use of port 443 on the client side for for development, and  for production
  • SOAP or REST requests to these web services are handled by the client-side API and are synchronous - meaning the request and results are all handled in one thread.
    • The benefit of this strategy is that the AvaTax web service does not contact the client at any time, as would be expected in an asynchronous architecture
  • Therefore all that is required for the client-side proxy server configuration is to set up a proxy pass rule that points to the domain name *

Note: Avalara’s web service does NOT support local host files (where IP's are mapped to Domain Names).  Any client accessing the AvaTax web service must use the DNS as a lookup service or risk connection failures.