AD Authentication failing on Linux Server

One Of my Linux Application Server, authentication is being done by the AD. On one fine day we got an issue saying the SSO (Single Sign-On) is not working for the webpage that is running on the server. I've been called Upon. So to start with I've checked following things to rectify the issue.

1. I tried to join the server with Domain again, which went fine.

net ADS join -U <User> -S <AD Server>

2. Then find out that one  of the Important service for AD Authentication is not running. So started that.

root@server1:/etc/rc3.d# ./S03winbind start
[ ok ] Starting the Winbind daemon: winbind.
root@server1:/etc/rc3.d#

3. Then joined the App server to domain again.

bingo , that worked like charm.