The left side of the address bar contains a button you can click to get information about that site. The button usually has a little mini-icon for the site and (if it's an encrypted site) the site's name. When you are on the site in question, click that button then click the "More Information" button on the dialog that appears. Alternatively, you can use the Tools menu and click "Page Info". Once you do that (either way) click the "Security" tab at the top and you will be able to click a button to view saved passwords for that site. Delete the incorrect password from that list. You can then log off the site and log back on to have Firefox offer to remember the new password.

Firefox should offer to store the correct password if you remove and fill the correct the password after Firefox has filled the password field with the wrong password. You can also highlight the user name in the drop down list of the name field on the web page and press the Delete key to remove that entry.

• http://kb.mozillazine.org/Deleting_autocomplete_entries