I have configured Identity server in my SharePoint 2013 environment for FBA users. The external users were displayed when we type full name in people picker. As it was not verifying my users until we enter full name, I tried below link solution to make it work:
But it didn't work. So I removed the solution from my environment. But it causes me below error when I open people picker dialog:
An error has occurred in the claim providers configured from this site collection.
Now it's not even validating windows users. I googled this and found this could be fixed with alternate access mapping settings. I have done this settings but the issue still persist. Is there anything else that can fix the People Picker dialog?