WHMCS is a bill management system commonly used by hosting providers. The latest version is currently 5.1.3, and the highest version downloaded from the official user center is 5.1.2. Since the launch of version 5.1.2, many friends have been eager to update. Although they encountered some problems, including language packs, Alipay plug-ins, etc., they have been basically solved. The problem I am talking about today is the official release of 5.1.2 Problems you may encounter when installing a new version.
Problem Description
When the user downloads WHMCS5.1.2 and installs it, log in to the backend, click Payments→Payment Gateway (Chinese menu: Payment→Payment Interface), the page will be blank, and only prompt: Module Not Activated
problem causes
This is caused by a problem with the PayPal payment interface file in the official WHMCS5.1.2 version.
Solution
Modify the /modules/gateways/paypal.php file in the WHMCS installation directory. For VPSAA customers, please log in to your user center and find your WHMCS hosting product, detail page, and download additional products. The modified files can be transferred to the relevant folder for overwriting.