From the Project Homepage:

1. Click the Project Tools link on the left hand menu.
2. Click the Forums button in the main body area.
3. Click the icon to the left of the Forum Category you wish to make this change to.
4. Click the Identify By Username check box so that it is no longer checked.
5. Click the Update Forum Category button at the bottom of the page.

You have successfully modified Forum Posts to display Username instead of Full Name.

Requirements

• Manage Forums Role
• Existing Forum Category

Notes

• This setting also determines if Full Names or Usernames are displayed on a Forum Post Edit (displayed at the bottom of a post along with when the Edit was made).