02-13-2020 09:58 AM
Bot printers need to be unplugged to restart even though they are wirelessly connected to a network and the 7640 is connected to a fax line.
02-17-2020 11:23 AM
Welcome to the HP Support Community.
You can't disable the sleep mode
After initial setup of printer, the printer will enter the Sleep mode after five minutes of inactivity.
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