So Roman calls me up this past week and asks me for new Mezuzah Scrolls and I ask him if he just moved in to a new home. He says no, his Rabbi told him his mezuzahs are not kosher and he needs new ones. By the way he asks, what does it mean that they are not kosher? aren't all mezuzahs kosher?
Roman, is not alone when asking that question and many people wonder what this term "Kosher" vs "Not Kosher" in regards to a mezuzah means. Its not like a chicken that needs to be slaughtered correcntly or milk that needs to be watched from the milking process, so what does kosher by a mezuzah really mean.
In order to answer this you need some basic backround of how the mezuzah is born so to speak. The first thing to know is that your mezuzah needs to be written on authentic real parchment, not paper or parchment feel like paper or any other leather like material.
See Mezuzah Scrolls here