...
- Extract the module archive which you downloaded from the client area.
- Upload the module to your WHMCS installation.
- Go to the WHMCS Admin backend, click on Setup → Addon Modules and activate the module.
- Click on Configure and do configure the values which you want to edit or leave it at the default values. At the point "Full Access IDs" you can specificate which Admins should have access to all generated PINs.
Accounts which are not listed will have to use the search mask to lookup the pin. Admins must be specificated by their ID. - At "Access Control" select "Full Administrator".
If you are using WHMCS below version 6 you need to add a menu entry at your WHMCS template which links to https://yourdomain.com/index.php?m=supportpin
On WHMCS v6 or above a sidebar widget is available, thereforce you do not need to add a link to the module page.