Bug 39927 (FormsAuthentication) - FormsAuthentication.Encrypt throws Null reference exception
Summary: FormsAuthentication.Encrypt throws Null reference exception
Status: NEW
Alias: FormsAuthentication
Product: Class Libraries
Classification: Mono
Component: System.Web (show other bugs)
Version: 4.2.0 (C6)
Hardware: All All
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2016-03-26 22:46 UTC by Tomasz Juszczak
Modified: 2016-03-26 22:47 UTC (History)
1 user (show)

Is this bug a regression?: ---
Last known good build:

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Description Tomasz Juszczak 2016-03-26 22:46:35 UTC
Encrypting FormsAuthenticationTicket throws Null reference exception at System.Web.Util.UrlUtils.Combine(String basePath, String relPath)

//Compile ready program used .Net 4.5 as a base
using System;
using System.Web.Security;
class Program
        static void Main(string[] args)
                FormsAuthenticationTicket formsTicket = new FormsAuthenticationTicket(
                var token = FormsAuthentication.Encrypt(formsTicket);
            catch (Exception e)
                Console.WriteLine(e.Message + e.StackTrace);


Example output from .Net

This happens on 4.2 SR2 as well on Beta channel