一、以下链接为 官方下载 可以自行进行改版本号进行下载
版本号查看 https://download.whmcs.com/

下载
V8.4.1 https://s3.amazonaws.com/releases.whmcs.com/v2/pkgs/whmcs-8.4.1-release.1.zip

V8.3.2 https://s3.amazonaws.com/releases.whmcs.com/v2/pkgs/whmcs-8.3.2-release.1.zip

V8.2.1 https://s3.amazonaws.com/releases.whmcs.com/v2/pkgs/whmcs-8.2.1-release.1.zip

V8.1.3 https://s3.amazonaws.com/releases.whmcs.com/v2/pkgs/whmcs-8.1.3-release.1.zip

V8.1.2 https://s3.amazonaws.com/releases.whmcs.com/v2/pkgs/whmcs-8.1.2-release.1.zip

V8.1.1 https://s3.amazonaws.com/releases.whmcs.com/v2/pkgs/whmcs-8.1.1-release.1.zip

V7.10.3 https://s3.amazonaws.com/releases.whmcs.com/v2/pkgs/whmcs-7.10.3-release.1.zip

二、替换授权文件（License.php） 进行开心
路径为 \vendor\whmcs\whmcs-foundation\lib\
开心文件下载 （License.php）
License.rar