Can these just die? Printer is refusing to recognise the cartridge and hence wont do anything

Take a look at cleaning the contacts on the cartridge / printer – it might just be a dodgy contact.

They can yes.

I had one that I knew was full but it wouldn’t work. I bought a widget that resets the ink levels in the cartridge – for use by people who refil their own – and it worked a treat. Cost only a few quid less than a new cartridge, but at least I wasn’t throwing good ink away.

EDIT: some cartridges for super cheap printers are actually the print head and cartridge combined together. Therefore they contain lots of gubbins that could quite easily go wrong I suppose.

Tried cleaning the contacts, but still dead. Think its about 1/2 full, no way of checking till it gets recognised again.
I hate the cost of HP ink enough already, this is not helping!

I had a printer which told me that the cartridge was outdated. Refused to acknowledge it, Eventually had to reset the date on the printer. That was HP

You should get a Brother or an Oki printer instead. 🙂