Terminal Password Issues

[gold_finger]

Just posting this here (way after this post has already stopped) just in case someone reads through having same type of problem as OP.

While testing something unrelated to this post for someone else, I ran into same problem in a VirtualBox setup of LL.  I could enter the password as normal in the terminal for admin activities that did not involve invoking a GUI.  There was no problem for instance installing a software package with a terminal command -- sudo apt-get install XYZ_package.  However, when I tried to open a GUI program with admin rights, it would not accept the password and kept proclaiming that it was wrong and telling me to try again.  For example, opening a text file as root with gksu leafpad /etc/fstab, would NOT take the password when entered.

It turned out to be because the gksu-properties were set to "su" instead of "sudo".  So to fix just do the following:
*  Open a terminal and run

Code:

gksu-properties

*  Under "Behavior"/"Authentication Mode" -- select "sudo" from the drop-down list; then "close".
*  That's all it took to get the password accepted for admin activities that invoke a GUI application.

Not sure if this was the OP's problem, but it very well could be for others who look here for answers to this problem.