How to fix WHMCS error Call to undefined method WHMCS\Http\Client\HttpClient
WHMCS Error:
Error: Call to undefined method WHMCS\Http\Client\HttpClient::requestAsync() in
Rename vendor/ and modules/ folders
root@server [/home/user/public_html/hosting]# mv vendor/ vendor_old root@server [/home/user/public_html/hosting]# mv modules/ modules_old
Upload fresh appropriate WHMCS version files into temp folder, for example: whmcstemp/
Copy vendor/ and modules/ folders from whmcstemp into your WHMCS installation folder:
root@server [/home/user/public_html/hosting]# cp -rp ../whmcstemp/vendor/… Read the rest