If you're seeing a 'No Connection Error' message when trying to get into your administrative area of your WHMCS, this means your WHMCS instance if unable to connect with the WHMCS licensing servers. This is commonly a CURL or DNS resolution problem, these are essential items in the use of WHMCS and is something your server admin will need to investigate and correct.
- CURL - CURL is an extremely important part of WHMCS and is needed for a number of the operations performed such as server connections etc.
- DNS - DNS is a vital part of internet functionality in order to be able to resolve hostnames of servers, domain name lookups, and licensing. Ensure your DNS resolve whmcs.com to the correct IP address.
A connection test can be accessed by adding the following suffix to the admin login.php page:
?conntest=1
For example: https://www.yourdomain.com/whmcs/admin/login.php?conntest=1
This will attempt to perform a cURL connection from your server to the WHMCS license servers and display the output on-screen. If any errors occur, they should be provided to your server admin/hosting provider so the conneciton issue can be corrected.