Expression Engine 2 disallow screen names add-on
Type of add-on: Extension
Likes already received: 4
Disallows anonymous users to use registered and actively used screen names.
DownloadingClick here to download this add-on
Unzip the downloaded zipfile and upload the disallow_screennames directory to:
Go to the Add-Ons > Extensions section of your control panel and enable the Disallow screen names extension. Access the settings screen and provide your own custom error message.
Since this is an extension that hooks into the comment module, there's nothing you have to do but install it.