If your HP Deskjet 3721 printer starts to print slower or produce errors, it may need a good cleaning. There are a few different ways to clean your HP Deskjet 3721 printer; each has its benefits and drawbacks. The original article is titled: The best way to clean your HP Deskjet 3721 printer: Step-by-step guide with pictures. Here are the steps:

  1. Open the top cover of the printer.
  2. Remove any obstructions inside the ink tank by removing the clogged ink cartridges and/or waste toner cartridges. Before continuing, clear any excess ink or toner from around these parts.
  3. Gently pour some white vinegar into the bottom of the printer’s drum and turn on the power switch to start rotating.