How to turn off e-mail notification when adding new users in Quality Center?

Having you right here, I believe you are a project administrator who receive email notification like below before.

From: xxx
Sent: Monday, January 01, 2015 01:00 AM
To: yyy
Subject: User added to project Sample_Project

This is an automatic message sent to you as an administrator of project 'Sample_Project' in domain 'Sample_Domain'. The following users were added to the project by the site administrator 'You' (by QC server XYZ):dummy_user

It will be like a spam when the amount of users added is a lot. So, action on below:

By default email notifications are sent to the project administrators when new users are added and removed from a project in Site Administrator. 

AUTO_MAIL_USER_NOTIFICATION is an optional Site Configuration paramater to toggle the notification functionality on and off. 

This parameter enables you to prevent Quality Center sending automatic email notification to project administrators when users are assigned or removed from a project in Site Administration. 

If this parameter is set to "N", then automatic notification is not sent to project administrators. If this parameter does not exist, is empty, or is set to "Y", then automatic notification is sent.

To disable automatic notification perform the steps below:
1. Login to the QC Site Administrator
2. Navigate to the Site Configuration Tab
3. Click the New Parameter Button
4. Enter AUTO_MAIL_USER_NOTIFICATION for the parameter field
5. Enter N for the value field

This is the sample result when it is done, and tested working. 

Cheers. :)