If you do not possess these items, you can find these items easily in most department stores or pharmacies, Simply dampen the swab in the rubbing alcohol. Make sure to only apply a light amount, Take the now damp cotton swap and insert it into the insertion gap. Once inside, wipe around the copper contacts in a rectangular motion. 

Be careful, but also be firm with your cleaning. Repeat this step (making sure to replace your swab each time) until you do not see any dirt on your swab

,, Air drying is the best recommendation. It should take no more than 5-10 minutes.
Acquire the cotton swabs and alcohol.
Dampen cotton swab in alcohol.
Wipe around copper contacts with alcohol covered cotton swab.Inspect cartridge for debris.
Allow cartridge to dry before you try it.
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