If your inkjet or bubblejet printer has clogged printheads there are 2 possible reasons:

1. Ink has dried in the nozzles; or
2. Foreign matter has blocked the holes in the nozzles.

If 1, it is important to note that although genuine inks have anti-clogging agents in their formulation, if you have not used your printer in a long time the ink will dry up in the printhead. With genuine inks a couple of head cleans will usually get the ink flowing again. If you are using refill or compatible cartridges more aggressive head cleans may be necessary. You may need printhead cleaning solution. The best way to stop ink drying in the printhead is to use your printer every week. Just print out a test page which will use black and colour.

If 2, this is caused by foreign matter in the ink - always from small unfiltered particles from refill ink or lower quality compatible cartridges manufactured in a dusty environment - or the printhead collecting paper dust from poor quality paper, or the printhead picking up muck in an overfull parking station.

What is a parking station? This is where the printhead sits when the printer is not printing, usually on the right hand side inside the printer. There is a small rubber cap here which sits under the printhead to protect and prevent it drying out. On most printers it also provides a cleaning function and there is a lot of waste ink in this area- so it is the perfect place to collect dust and muck. You can get a cotton bud in there and clean it by switching the printer off then on, and then when the printhead moves away from the parking station switch the printer off at the wall. You will then be able to access this area for cleaning.

If foreign matter in the ink has blocked the printheads and your printhead is fixed into the machine, put new original cartridges in your machine as this will usually dissolve any particles in the printhead. If your printhead is removable, take it out of the machine and sit it in about 5ml of very hot (not boiling!) water for a few minutes. Dry thoroughly and re-insert into the machine and do a couple of printer head cleans. Repeat until the nozzles are unblocked. Always use good quality inks or compatibles in your printer - original inks are always best.

If you open your printer and you can see a fine white powder inside the machine, this is paper dust. This is getting into the print nozzles! Always use good quality paper and once in a while use compressed air to clean out the inside of your printer (use a can of compressed air, not compressed air from a compressor - or you'll blow away the electronics in your printer!).