When Removing Mezuzos for Checking the old nails, screws and tape previously used to affix the Mezuzos may be discarded. However, Mezuzah cases and Mezuzah wrappings if no longer needed should be treated as sacred material and require genizah/interment, after their use.

It is preferred to have all of the mezuzahs returned to their original doorposts, or at least to the same type of entrance way (i.e., from one bedroom door to another, or from one archway to another) in order that you don’t lower the status of a Mezuzah that was once on a door required Midoraisa (Biblical) to a entrance way that is only Rabbinical.

A practical suggestion: when removing the mezuzahs, label each mezuzah case with a number (using masking tape or the like). Tape an identical number on the doorpost from which it was removed. When the mezuzahs are remounted, match the numbers from your cases to the numbers on the doorposts.

When removing Mezuzos for Checking, or renovations are being done, or for any other reason when the Mezuzah is remounted, the blessing should be recited only if the Mezuzah was off the doorposts for at least one night. If you are also adding new Mezuzahs at this time, it is preferable to recite the blessing on a new one (providing that it is mounted on a door that requires a blessing).

Computer checkingIn addition to a Sofers examination, we strongly recommended you to have a computer checking done as well.

Although examiners do the best they can, humans can make mistakes which the computer can catch. However, it is not a substitute for the manual examination, for although the computer can successfully catch missing and substituted letters, it can not determine letters with a problematic shape if they are Kosher or not, or do the actual repairs if necessary. This can only be accomplished through a meticulous manual examination by a qualified Sofer.

The cost for a computer examination is minimal and a one time expense. If you have never had your Teffilin or Mezuzos computer checked, it is advisable to do so the next time you have them examined.