Select [Tools] in the menu bar and then select [Options] from the drop down menu.
The Options dialog appears.
              The Options dialog can also be displayed by
              clicking the
               icon in the toolbar.
              icon in the toolbar.
            
Select [Search Engine] > [Mascot] in the Options dialog.

Enter the URL in [Mascot URL].
Enter the user name and the password if necessary.
Click [OK].