If you have selected to use the enom plugin and you receive the following error message when searching for a domain:
Could not contact registry to lookup domain
Check that your server has php compiled with both curl and ssl support. The OpenSSL libraries must also be installed on the server so that your server can connect to Enom's https server.
If you have confirmed that php is properly configured with curl and openssl support, check the Path To Curl setting under System setup -> Settings -> Presets . Leave the "path to curl" entry blank so that curl as configured in php will be used.