I sometimes need to change the settings (i.e the usergroup) of a user via the User Manager in the Joomla backend. Before, I remember I could easily achieve this by changing the fields required and clicking "save".

For some reason (even on a fresh installation of Joomla), whenever I try and do this, I get the following message:

Warning

The passwords you entered do not match. Please enter your desired password in the password field and confirm your entry by entering it in the confirm password field.

I can't simply go ahead and reset the password, so how can I update their settings without having to confirm a password that I don't know?