blondie10 wrote: but who cares you're the mvp after all, though from a quick check on Microsoft's MVP web site your not listed, That's because I never wrote the thing and enabled it for public view. blondie10 wrote: Also Public / Private cryptography is asymmetric not symmetric, Sorry, I was thinking 'asymmetric' and typed 'symmetric'. blondie10 wrote: I don't understand about sending data in reverse, does the remote system use the public key to encrypt the message and my system then uses the private key to decrypt it? If this is so does'nt this mean any user can send me a message as the public key is, well, public? Yes, to both questions. The only difference between Public and Private keys is the arbitrary choice of which one you give out to the public. blondie10 wrote: Now perhaps the only answer to the problem at this level of security would be to objfuscate the code. Obfuscationis about the best choice you have that doesn't cost $,$$$. Dave Kreskowiak Microsoft MVP - Visual Basic