The dreaded “Invalid user name and password combination” error that can be given in Directory Utility, can be the biggest pain for us Admins. I found these three commands allowed me to re-bind successfully. Give it a try and let us know your results. These must be done as root or with the sudo command. I also had to reboot after these commands were given.
rm -rdfv /Library/Preferences/DirectoryService
rm -rdfv /var/db/dslocal/nodes/Default/config
killall -USR1 DirectoryService