Years ago I called them to get an RMA on a scanner that had a fingerprint on the INSIDE side of the glass. They wanted me to disassemble it and charge me $70 for the knowledge on how to do so. Fuck HP.
Their sales reps that hang out at Microcenter would actually not stop talking to me. I literally walked past them and wouldn't make eye contact. They followed me through the whole section. It wasn't until I approached an actual MC employee and said, "I will never buy an HP product. Can you help me?" The HP guy still followed us while I bought another printer! Fuck HP.