I have a SharePoint 2010 web application migrated to SharePoint 2013. this is a classic mode web application, we are not using claims, my client doesn't wants it ( Don't ask why?). I had other web application migrated as same process but i can add users in them. but in this i am not able to. I can add users and find users in the web application in central administration. But not in the web application itself.
I am not sure what changes i have to make so that it starts picking or finding users from the people picker. any ideas.