Brother Customer Service provided instructions for factory reset:
1. Turn printer off
2. Hold down button on front panel (HL-730 has only one button)
3. While continuing to hold down the button turn the printer on and wait
until the drum light comes on.
4. Release the button then hold it down again until the drum light comes
on again. When this occurs release the button and the printer is reset.
I have no idea whether this is specific to the HL-730 or to many models
of Brother printers - I added the parenthetical remark that the HL-730
has only one button.
I had tried to contact customer service without success prior to my
initial posting. When none of the suggestions worked I tried again and
got a response on the next business day. Either I made an error in my
initial enquiry or I was lucky this time to get someone who knew how to
factory reset a 10 year old printer.
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