ASP.net IIS - if intergrated authentication fails, fall back to form based?

It should be.  Just check if the currently logged in user is a member of that AD group and, if not, redirect them to a page where they can log in.  

Here's one way to do this:

 Public Function GetADGroups() As ArrayList
    '##########
    '### Returns an array of Active Directory groups the current user belongs to

    Dim aryGroups As New ArrayList()
    For Each irefGroup As System.Security.Principal.IdentityReference In System.Web.HttpContext.Current.Request.LogonUserIdentity.Groups
      aryGroups.Add(irefGroup.Translate(GetType(System.Security.Principal.NTAccount)).ToString.ToLower)
    Next
    Return aryGroups
  End Function

You could modify my code to check for a particular group and do something based on whether or not it exists in the list.  I do things a little differently, but this should accomplish what you want.

can you show me this function in c#?

for example..

if (ADUser.groups != "GROUPNAME")
{
  redirect loginform.aspx
}
intergrated Authentication;

Courtesy of http://www.developerfusion.com/tools/convert/vb-to-csharp/

public ArrayList GetADGroups()
{
      //##########
      //### Returns an array of Active Directory groups the current user belongs to

      ArrayList aryGroups = new ArrayList();
      foreach (System.Security.Principal.IdentityReference irefGroup in System.Web.HttpContext.Current.Request.LogonUserIdentity.Groups) {
            aryGroups.Add(irefGroup.Translate(typeof(System.Security.Principal.NTAccount)).ToString().ToLower());
      }
      return aryGroups;
}

ok so i can do an if statement to check for ad groups then if a user is not in ad and i redirect to the login form how will the web config know to take the form credentials and not the integrated credentials it would take for the ad group?

Thanks

thanks