It would take many pages to list all of HP's sins here. This is a company that ships printers with half-full ink cartridges and charges more than the printer cost to buy a replacement set. The company that won't let you print a black-and-white page if you're out of yellow ink. The company that won't let you scan or send a fax if you're out of any of your ink.

They make you "recalibrate" your printer or "clean your heads" by forcing you to print sheets of ink-dense paper. They also refuse to let you use your ink cartridges after they "expire."

HP raised the price of ink to over $10,000 per gallon, then went to war against third-party ink cartridge makers, cartridge remanufacturers, and cartridge refillers. They added "security chips" to their cartridges whose job was to watch the ink levels in your cartridge and, when they dip below a certain level (long before the cartridge is actually empty), declare the cartridge to be dry and permanently out of use.

Even if you refill that cartridge, it will still declare itself to be empty to your printer, which will therefore refuse to print.

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Even sleazier: HP pushes out fake security updates to its printers. You get a message telling you there's an urgent security update, you click OK, and your printer shows you a downloading/installing progress bar and reboots itself. As far as you can tell, nothing has changed. But these aren't "security" updates, they're updates that block third-party ink, and HP has designed them not to kick in for several months. That way, HP owners who get tricked into installing this downgrade don't raise hell online and warn everyone else until they've installed it too, and it's too late