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Restart the print spooler (you will need to open the Services module as the Administrator)
Ask the store to turn off the printer
Then ask them to physically disconnect the power cable from the wall
Ask them to turn the printer back on for about 10 seconds whilst the printer is unplugged
Then get them to switch the printer back off again
Then ask the store to plug power lead back in
Then ask the store to turn the printer back on again
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