I have several different sharepoint 2013 website that only use Claims based Authentication with NTLM but in IIS all of them had both windows authentication and Forms Based authentication enabled. The sites were working fine but I know this is not a good setup so I went to remove the forms based auth. When I did I lost access to all the sites even though I am not using forms based auth. I found that if I change the web.config setting for allowanonymousimpersonation to false that I was able to get in to all the site again. Problem I have now is that when I try to edit a library items properties I am prompted for a password three time in a row then it lets me in to edit the properties. Any one have any ideas what is going on?
Thanks.
