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This may be due to your external http traffic being routed through a proxy server.
If your company uses a [http://en.wikipedia.org/wiki/Proxy_server Proxy Server] your frevvo Form Proxy Server, your Form Server may not be able to communicate with the license server directly. frevvo has has web configuration parameters to enable communication from the Form Server to the license server via your proxy. Edit the following parameters in <frevvo installdir>/frevvo/tomcat/webapps/frevvo/WEB-INF/web.xml or override them at the container level by putting the parameters into frevvo.xml, eg: on Tomcat in tomcat/config/catalina/localhost/frevvo.xml.
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