Receiving login prompt using integrated windows authentication
Solution:
Don't create mistakes on your server by changing everything. If you have windows prompt to logon when using Windows Authentication on 2008 R2, just go to Providers and move UP NTLM for each your application. When Negotiate is first one in the list, Windows Authentication can stop to work property for specific application on 2008 R2 and you can be prompted to enter username and password than never work. That sometime happens when you made an update of your application. Just be sure than NTLM is first on the list and you will never see this problem again.
Thanks to Slo
