OK, I eventually Googled enough to find out that the secret password is the printer's serial number, however, it will not keep the serial number - you must enter it each time!!
How do I make the Web Page view store the password? I have seen it said you can change this password, but even the procedure for that seems to be hidden...
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The administrator password will not be saved if your web browser settings are set to not store passwords. If this is the case, you must enter it each time you wish to access the Remote User Interface.
To change the password and for more information regarding the password for your PIXMA MG7720, please use the following links:
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