Printer is online but print queue shows offline - but not for all computers

[AHG]

We have a Cannon Pixma MG7120 printer. My daughter and I can both print wirelessly from our computers (Toshiba and Dell respectively) but my husband's computer (also a Dell) gives him a message that the printer is offline and to make sure it is turned on.

I have successfully printed from my computer within minutes of him getting this error. 

Firmware on the printer is up to date. Next steps? 

[Ramona]

Hi AHG,

Resetting your network may resolve the issue being experienced. To do this, please follow these steps:

1. Turn off the printer and unplug the power cord, then turn off all of your computers.

2. Unplug your wireless router for at least 60 seconds, then plug it back in.

3. Wait 5 minutes, then plug the printer back in, then turn it and all computers back on. 

Please attempt to print again from all computers.  Should you still experience difficulty, we ask that you please contact a Canon technical support representative here for further assistance. A representative will be happy to assist you free of charge.