I want to change the administrator password

Hi all,
I want to change the administrator password.
When I am logged on as administrator and try to change the password I receive the following message;
1359: An internal Error has occurred. Please consult your system administrator.
I used Google and discovered there should be an error in the log
Event 1126 Unable to establish connect with global catalog But it was not there…
I have searched the help the best I can, but I can´t seem to find a minimum or maximum time for the current password.
If I change to the max password to one day would it prompt the password to be changed or would error 1359 appear again?
What can I do?
