Re: Epson DX4400 cartridge change
I've used several Epson printers, and in every case, there's a button combination you can press on the printer that will move the cartridge holder so you can see which cartridge needs replacing. I would be surprised if the DX4400 did not have this feature.
As to checking ink levels, it's not an OS function; instead, it's a driver function. Epson distributes their ink monitoring utility with their Windows installations, but does not (AFAIK) make such a utility for Linux.
What I've used in the past (and still use) is mtink. You should Google for this, download and install it, and go through the steps to have it find your printer.
Ubuntu 16.10 Mate, Mint 18 Mate; MS Win 8.1, MS Win10 Pro.
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