Change PvP Settings

Before following these steps, make sure to stop your server first. This is to avoiding breaking anything on your server while you edit. 

Step 1: Head to your game panel and look for your File icon on the left hand side.
// Photos to be added on AH 2.0

Step 2: When you are in you files, scroll down until you see a file named: serverconfig.xml
// Photos to be added on AH 2.0

Step 3:  Open the file and look for the line that says: <property name="PlayerKillingMode" value="3" /> . When you have found this line, you just need to change the number in the Value area. 

Before:
<property name="PlayerKillingMode"                value="3" /> <--- Everyone can kill each other

After:
<property name="PlayerKillingMode"                value="0" /> <--- No one can kill each other

There are 3 settings for Server Visibility ranging from 0 to 2.
Each number has its own setting:

0 = No Killing: Players cannot damage one another under any circumstances.

1 = Killing Allies Only: Players can only damage each other if both agree to it by adding each other to their Allies list using the in game players menu.

2 = Killing Strangers Only: Players can damage each other UNLESS they are Allies.

3 = Killing Everyone: Players can damage everyone, regardless of Allied status

//Photos to be added on AH 2.0

Make sure to save before exiting the file.

After Completing these steps, you can now go and start you server.

//Photos to be added on AH 2.0