how does one contact HP to tell them the ENVY 7640 is the worst printer I have ever purchased. Every time Windows 10 upgrades the printer stops working, or this last time just disappeared. I tried to reinstall it with no success. I then used the printer doctor and the latest version of the doc did reconnect and install the printer. No other printer I have ever had has this much trouble. Hp apparently doesn't really know how crappy the product is because I cannot find a place on their website to communicate with them unless I pay them money. Last HP product ever