Unknown error code on HP printer 3721

[Richard_K1]

Any ideas on this error?

 Even after unplugging and restarting I can’t get my printer past this error. It’s 13 months old, just out of warrenty of course!!

Any ideas?

[A4Apollo]

Hi! @Richard_K1, Thanks for stopping by the HP Support Forums!

I understand you are getting E3 error on your printer.

Don't worry I'll try to help you out.

Did you make any changes to your printer?

Did you check if there is a paper jam on your printer?

Have you tried checking with a different ink cartridge?

Please try few steps recommended below.

Remove and then reinstall the ink cartridges

Reset the printer

Resetting the printer can clear carriage jam errors.
Turn the printer on, if it is not already on.
Wait until the printer is idle and silent before you continue.
With the printer turned on, disconnect the power cord from the rear of the printer.
Unplug the power cord from the wall outlet.
Wait at least 60 seconds.
Plug the power cord back into the wall outlet.
   NOTE:
HP recommends connecting the printer power cord directly to the wall outlet.
Reconnect the power cord to the rear of the printer.
Turn on the printer, if it does not automatically turn on.
The printer might go through a warm-up period. The printer lights might flash, and the carriage might move.
Wait until the warm-up period finishes and your printer is idle and silent before you proceed.
Try to print.

Clear all paper from the input tray
Remove all loose and jammed paper from the input tray area.

Make sure the carriage can move freely

Make sure the ink cartridges are correctly installed

Refer this article to further troubleshoot E3 issues with your printer. Click Here

If the issue still persists after trying out the steps it is a hardware issue with your printer.

Let me know if this helps!

Have a beautiful day ahead! 🙂

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[Richard_K1]

The print suddenly stopped half way through a one page print and hasn't come out of this E3 error since. I have tried as you suggested and all the options on the online manual but still no change.

[A4Apollo]

@Richard_K1, Thanks for prompt response and time.

I appreciate your efforts for writing back to us.

As you mentioned the issue still persists after trying out the steps.

If you have tried all the steps from the document. It certainly sounds like a hardware issue with your printer.

I will share you few details through a private message about the service options for your printer.

Please watch your inbox for more information.

Have a pleasant day ahead!

Take Care! 🙂