Why Can’t I Get My Key Copied?

If you are having trouble getting your key copied at your local hardware store, Ace Hardware, Home Depot or Lowe’s there may be several reasons why. We are frequently asked to duplicate hard to find keys and sometimes keys that are not supposed to be copied! In this post I’ll detail some common reasons why and how you might still be able to obtain a key copy.

1: Worn Key

When you copy a key on a regular duplicator there might be some small variances. These variances are caused by 1) the way the key is placed into the jaw 2) the calibration of the machine 3) the angle of the duplicator’s cutting wheel. Some cuts on the key might end up higher and some might end up lower. This might make the key duplicate out of tolerance enough to make the key not work. Some self-service key duplicating machines scan the key and correct these mis-cuts. However, they may make corrections when they shouldn’t which results in a key that will not turn the lock.

2: I/C Key

IC, interchangeable core, locks are used for various reasons. One a control key allows you to remove the core allowing to quickly rekey the lock. Another benefit is increased security. Ideally, these keys should be punched not duplicated. An SFIC punch is an expensive dedicated piece of equipment that even many locksmiths don’t have. It IS possible to manually duplicate these keys but they often do not work 100% correctly. The tolerances on SFIC keys/ SFIC cores are very tight.

There are several manufactures of these key systems including: Best, Falcon, and Arrow and tens of different keyways available. Many of these keys do not indicate what keyway they are. Thus, in order to duplicate the key a locksmith first has to determine what type of key it is. SFIC locks also come in restricted keyways.

3: Locksmith-Only Key

In order to help control unauthorized key duplication property owners and business managers sometimes use what are called locksmith-only or restricted keys. There are dozens of keyways available only to locksmiths through distributors. They really do only sell these keys and blanks to locksmiths. Some examples of these keyways are LSA by LSDA and MX / MX Alpha by GMS.


There are at least three such keys on the market today:  and HS by Hardware Agencies. These key blanks are only sold to locksmiths and security professionals registered with authorized dealers of security products and access control solutions like, for instance, the International Distribution Network. If you have an LSA, MX10, or HS key, you will have to locate a locksmith that is registered to sell the blanks for your restricted key.

4: High Security Key With An Open Keyway

Business managers and property owners sometimes want locks and keys with additional security features like pick resistant, bump resistant, and/or drill resistant. Medeco‘s 00 keyway, CX5‘s ZOL keyway, and Schlage‘s Everest C123 keyway are all popular open keyways found in the field today. These locks can typically be bought from distributors that sell to the general public. So seeing a Medeco lock on a door doesn’t automatically mean that a locksmith installed the lock.

5: DND Key (Do Not Duplicate)

Even the most common key blanks are sold with a DND or DO NOT DUPLICATE stamped or embossed on the key. This stamping is on what’s called the bow or head of the key – that’s the part of the key that you hold. If you look and standard keys you’ll find that the bow of the key has a unique shape. These different shapes are part of the way locksmiths use to identify what type of key the lock is. DND keys typically come in what’s referred to as a neutered bow. The head of the key is a simple rectangular shape. This prevents someone from guessing the key by looking at the head of the key. Many seasoned locksmiths can look at the grooves on these keys and determine what type of key it is. Additionally, common keys like SC1 SC4 and KW1 can be read by key kiosks. So if you’re looking to prevent unauthorized copies this method is simply not enough anymore.

6: Old Key

Some older homes and even businesses have locks that use older keys that are not popular anymore. Many antique locks used Corbin Russwin keys that many hardware stores don’t stock.