Not Printing and Orange Right Light Blinking

[Janis90]

Hi!

I have a few years old HP Deskjet 3630 that I use to print about five A4 pages per week for work. Never used colored ink, and have been only using the black ink replacing the cartridge once in a few months.

Yesterday I was printing just fine, but today when trying to print an invoice for a client I encountered a problem that I never seen before. When I press 'print', nothing happens, the document just gets queued, a Windows message 'Printer is in an error state' pops up, and out of three lights at the top of the printer panel the right one keeps blinking in orange. Also 'UU' is showing on a printer screen.

You can see the picture of the printer panel in the imgur link below:

[content removed]

When I tried to Align Cartridges, Clean Cartridges and Clean Printer through the HP printer app it said 'Device is busy'.

I've already tried:

1. Completely disconnecting USB and power cords from printer, computer, power outlet + uninstalling all printer drivers and removing the printer from Control Panel > Devices and Printers then shutting down my PC, plugging all cords in and turning PC and printer on again.

2. Removing both cartridges and gently cleaning their contacts.

3. Resetting the printer by holding Power and X button, then letting go X button and then letting go Power button.

4.  Scanning with HP Print and Scan doctor. It only offers to print a test page which obviously doesn't get printed.

I really doubt the cartridge is simply empty because throughout these years whenever I was out of ink the printer just printed blank or smeared pages instead of refusing to print at all.

I really don't want to pay for a new cartridge only to find out that the fault lies within the printer itself and not the cartridge.

Any help will be appreciated.