Is there a way to skip log on using code for an asp.net application?

If this is regular asp.net you need impersonation.

Here are my notes on this:

Both server and client must be in the intranet zone.
Code - note the iis configuration in comments:
            string EditorGroup = (string)ConfigurationManager.AppSettings["EditorGroup"];
            string AdminGroup = (string)ConfigurationManager.AppSettings["AdminGroup"];

            // Hosting web site must have:
            // Anonymous authentication disabled
            // Asp.Net Impersonation enabled
            // Windows Authentication enabled
            // appPool used must be classic asp.net appPool ( in advanced settings for web site ).

            string WithDomain = HttpContext.Current.Request.LogonUserIdentity.Name.ToString();
            string JustName = WithDomain.Substring(WithDomain.LastIndexOf('\\') + 1);

            bool IsAdmin = IsInGroup(WithDomain, AdminGroup);
            bool IsEditor = IsInGroup(WithDomain, EditorGroup);
            
Method to do isinrole
        private bool IsInGroup(string user, string group)
        {
            try
            {
                using (var identity = new WindowsIdentity(user))
                {
                    var principal = new WindowsPrincipal(identity);
                    return principal.IsInRole(group);
                }
            }
            catch
            {
                return false;
            }
            
        }

In web.config
  <system.web>
    <authentication mode="Windows" />

The isingroup stuff is checking whether the user is in a particular AD user group.

You can also check that in web.config

<system.web>
  <authentication mode=“Windows“/>
  <identity impersonate=“true“/>
  <authorization>
    <allow roles=“Your group“/>
    <deny users=“*“/>
  </authorization>
</system.web>

http://www.codeproject.com/Articles/175028/ASP-NET-Windows-Authentication-Authorization-by-Gr

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