A CRC isn't really a security feature - it's a way to validate that something wasn't tampered with. It's essentially a very simplistic hash.

A better choice for this sort of thing though is probably an MD5 hash instead which is more of a universal standard that is readily available with code standards.

As for Ed trying to replicate the SYS(2007) value - that's probably not going to happen if the algorithm used to produce it is non-standard.

+++ Rick ---

>>yes that is exactly what I found - several other items that claimed to be crc16 - some not even agreeing with each other - but none of them agreeing with sys(2007)
>
>What are you using CRC for? It's pretty much useless for cryptography or security purposes.
>
>Some time ago Craig Boyd released VFPEncryption: http://www.sweetpotatosoftware.com/spsblog/2009/08/09/MajorVFPEncryptionUpdate.aspx
>
>That offers some serious cryptographic functions. I imagine most if not all of those are part of .Net without any further effort needed by you.