4 Replies Latest reply on Nov 11, 2014 2:58 PM by deninger

    License Keys


      Is there a good way to both create and verify a "license" code for use a FM app?


      What I am looking for is to enable a feature based on a license key tied to a user or business name such that


      1) the key can be generated by me and

      2) the key can be validated by FM Pro given the token (business name or use name) and the type of license it is


      EG: Username: Towncrest Pharmacy , License Type = feature1 Generated Key = AAAAAAAA-BBBBB-CCCC (or some such nonsense)


      Then, with Filemaker Pro I could call a custom function that, given "Towncrest Pharmacy" and the above Key, returns a valid or invalid response


      Any suggestions would be most welcome.



        • 1. Re: License Keys

          Many years ago (FM 6) I built a system that once purchased, I would generate a license code based on a user name. I built a calculation that would take the user name and perform a routine to generate a code. When the user put in both their name and the code, the system would be unlocked. If the entered user name didn't generate the same license key as what I sent them (and was typed in) they remained in a demo mode.


          Not the best way to do it as it didn't stop the user from using the same info on another computer or give it to somebody else. It also had the calculation in the schema - not optimal either. Doing something like this in a custom function might be a bit better. They didn't exist at the time I created my system.


          For this runtime solution it was enough.

          • 2. Re: License Keys

            It depends on how and where you intend to verify the code.


            If you are using lookup tables, ie, then a search for user name and the

            licence type is will produce a found count, ie,  a boolean value.


            If you are using some sort of re-encoding scheme then your user name and

            the licence type can be combined with a Luhn algorithm to produce a

            check digit.



            • 3. Re: License Keys

              Hi Mike,


              If you should happen to go down the path of rolling your own registration code generator/validator, Todd Geist has a blog post on FileMaker and MD5 Hash that may be relevant to your endeavor:




              I have not personally used the above yet -- I've only made a mental note about it, thinking it might be helpful for situations that require some kind of validation mechanism.


              Kind regards,



              • 4. Re: License Keys

                This is exactly the type of function I was looking for! I was afraid that I was going to have to resort to another plugin to do this.


                While this type of key is certainly not super secure, it does provide a reasonable level protection from a customer enabling a feature they have not paid for.