The following article will cover the steps needed to add a password on your DayZ Server Hosted By Host Havoc.
1. Log into your game panel.
2. Stop your service if it is running.
3. Click on in your game panel and then click on for the serverDZ_By_HostHavoc.cfg file.
4. Locate the password = "";
and add your desired password between the two quotation marks and click on
Example - password = "mypassword";