I extended current web application to extranet and initially used windows based authentication. Now the business unit wants form based authentication for the extended extranet site. changing option only available for the main web app and not for extended web which is only shown in AAM (modified: actually extranet shows up when i click on authentication provider for the web app). Do I need to delete the extended extranded i created ealier (if yes how do i delete this, just to iis and delete the website or another way of doing this)? and go through extending webapp and pick form based.
Here is a good walk through for enabling windows and forms authentication on the same webapp.
If you want to get rid of the extended zone just delete web app in central admin and it will ask you what zone and if you want to delete associated iis site.