title: Extending MembershipProvider
body: <p><strong>Scenario:</strong></p>
  
  <p>Building an application for companies to enter information into.</p>
  
  <p>I need to extend the built-in membership provider in asp.net.  My unique situation is that I already have demographic information for each company, but NOT userid's and passwords for a web app.  I want to prepopulate the DB with the demographic information, send each company a unique pin number, and ask them to register with my application.  I want them to create a userid, email address and password, after they've "validated" who they are by entering the pin number that they received in the mail.  Yes, we'd be sending them, via snail mail, a unique pin number.</p>
  
  <p><strong>Problem:</strong></p>
  
  <p>Not quite sure where to start.  The problem centers around the fact that we already have demographic information for these companies and right now, it's not possible to use this new web application to update the demographic info, so we really don't want them to change it.  We also don't want just anybody being able to register an account and entering demographic information.</p>
  
  <p><strong>Questions:</strong></p>
  
  <p>Am I thinking about this the wrong way?<br>
  Is extending the membership provider the right way to go?
  What is the best way to handle this situation?</p>