How to disable invoice generation for 0.00 invoices

The short answer is we cannot disable. Some time ago I was looking for solution to NOT send (or even generate maybe) invoices with total 0.00 It is a bit weird for clients to see payment confirmation about their $0.00 invoices. They are kinda “free” invoices and they are marked paid instantly. So far I didnt find any solution and found a lot of similar requests on official forum thread. So here’s a hook to [...]

How to check existing client in WHMCS by email

Native WHMCS API allows us to register clients, but not to check if certain email is already in use. So this tiny function will help you to determine do you already have this client in your DB.

Introduction to custom WHMCS API functions

Are you not satisfied with default WHMCS API functions? In this little note I introduce you a very basic template for a custom API function.

Client details in WHMCS templates

In client area templates you can access most of client details for your needs. $clientsdetails is associative very handful array:

WHMCS native select_query function

There’s no reason to explain why do we need to make SQL queries inside custom files, modules etc. Most of examples on the net use mysql_query function. But sometimes it would be reasonable to use native WHMCS function select_query. Or at least to know how it works.

Client login depending on its status

I was testing what the client will see in his area depending on its status (Active, Inactive, Closed). I was wondering why I keep login successfully when client has “Closed” status? Again and again I changed status and saw the client is still able to login.

Autologin link to WHMCS in email

Most of you probably knows about great WHMCS AutoAuth feature, which allows us to create links to send user to its client area without prompting username and password. But what if you like to have such link sent in email?