HP has to do this to prevent issues with jets and more. If you get an outdated cart from a retailer then HP is known to replace these if you ask them to.
Since you didn't heed the install by date and cracked it open I can't be sure if HP will replace this one but do ask.
Bob
I have an HP C5280 photosmart inkjet printer which is about a year old. The printer uses #74 black and #75 color cartridges. This afternoon I had to replace the #75 cartridge, on the back of the box containing the cartridge I installed earlier today it said warranty ends February 2010, when I opened up the box and removed the cartridge from the box the date on the plastic bag containing the cartridge read August 2009 which is the install by date. I know it's about 3 months since the install by date but I went ahead and installed it anyway.
It wasn't long afterwards when I tried to print something I received an error message to check printer documentation, cartridge problem. Then on my monitor's screen another box popped up saying there was a problem with my recently installed #75 color cartridge, check printer documentation. I went ahead and removed the newly installed #75 color cartridge and installed another #75 color cartridge which had a better install by date, a July 2010 install by date with a warranty end date on the back of that cartridge's box of January 2011. The printer now seems to be working fine. This is a first for me. Does HP have built into their newer cartridges a chip or a sensor which will prevent the cartridge from working if the cartridge is installed in a printer past the cartridge's install by date?

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