title: Encrypt string in C# and decrypt it in Delphi
body: <p>I'm writing a web app in ASP.Net that creates a licence key for a Windows app written in Delphi. For simplicity I'm going to use a email address and date.</p>
  
  <p>I want to encrypt it in C# and email that info to the person then when the Windows app starts up the person enters in the encrypted string.</p>
  
  <p>Every time the Windows app starts it checks that licence by decrypting it and comparing to todays date.</p>
  
  <p>How can I do this to ensure the C# encryption will decrpyt succesffuly in Delphi?</p>