Hi John,
I had a similar problem and solved this by using MD5 encryption - do a few
searches on Google and you will find suitable examples. I generate a unique
Key string based on a number f parameters that I ask them to send me. This
does a comparison with the string that their entries will generate, and if
there is a match then the registered version loads. The application that I
distribute works with a server - hence the application is locked to that
server. Below is the function that I used:-
Imports System.Text
Imports System.Security.Cryptography
Module modEncrypt
Public Function HashData(ByVal s As String) As String
'Convert the string to a byte array
Dim bytDataToHash As Byte() = _
(New UnicodeEncoding()).GetBytes(s)
'Compute the MD5 hash algorithm
Dim bytHashValue As Byte() = _
New MD5CryptoServiceProvider().ComputeHash(bytDataToHa sh)
Return BitConverter.ToString(bytHashValue)
End Function
End Module
I call the function with somethin g like:-
txtKeyCode.Text = HashData(sServer & sVersion & sApplication)
txtKeyCode.Text is the Key that I send to them that makes a comparison to
the key genrerated in their application.
Hope this is self explanatory and that it helps you. It seems to work very
well for me.
Paul
<ne**@prodata.co.uk> wrote in message
news:66********************************@4ax.com...
Seems like the copy protection (ie licensing/antipiracy) tool that I
used with VB6 isn't very compatible with VB.Net. Anyone have a
recommendation for one that works well with VB.Net applications? Only
basic protection is really needed, so simple to use and cheap are more
important than absolute protection.
JGD
