NullReferenceException when trying to set registry permissions with C#

Question

I'm trying to set the below permissions on a registry key. But I get a NullReferenceException error when it tries. Being a novice makes this tuff. Throw in permissions (which have always confused me) and I'm stumped. Can someone tell me why I'm getting this? Thanks.

using System;
using Microsoft.Win32;
using System.Security.AccessControl;

namespace ConsoleApplication7
{
   class Program
   {
       static void Main(string[] args)
       {
           RegistrySecurity rs = new RegistrySecurity();
           string user = "Everyone";

           RegistryKey rk = Registry.LocalMachine.OpenSubKey(@"\SOFTWARE\Wow6432Node\123Test", true);

           rs.AddAccessRule(new RegistryAccessRule(user,
               RegistryRights.FullControl | RegistryRights.TakeOwnership,
               InheritanceFlags.ContainerInherit,
               PropagationFlags.None,
               AccessControlType.Allow));

           rk.SetAccessControl(rs);
       }
   }
}

enter image description here

It's failing to get the RegistryKey rk – Sam Leach Jul 17 '13 at 15:00 — Sam Leach, Jul 17 '13 at 15:00

score 1 · Answer 1 · edited May 23 '17 at 11:56

1

Try

@"\\SOFTWARE\\Wow6432Node\\123Test"

(double '\')

If not, try this answer.

edited May 23 '17 at 11:56

Community

1
1

answered Jul 17 '13 at 15:01

Sam Leach

12,746
9
45
73

score 1 · Answer 2 · answered Jul 17 '13 at 15:02

1

Most likely the nullreference exception is on the RegistryKey rk itself.

Is your application running as a 32-bit or 64-bit application? You shouldn't need to specify the Wow6432Node part and should just be able to reference @"\SOFTWARE\123Test

answered Jul 17 '13 at 15:02

Fishcake

10,496
7
44
72

score 1 · Accepted Answer · answered Jul 17 '13 at 15:11

1

This line is causing you error

 RegistryKey rk = Registry.LocalMachine.OpenSubKey(@"\SOFTWARE\Wow6432Node\123Test", true);

Place a debugger here and see if it has value or it is null. If it is null check that path is valid. If it is valid do it like this

RegistryKey rk = Registry.LocalMachine.OpenSubKey(@"\\SOFTWARE\\Wow6432Node\\123Test", true);

answered Jul 17 '13 at 15:11

Ehsan

31,833
6
56
65

Thank you. The debugger tip was what I was forgetting. – JimDel Jul 17 '13 at 17:23

NullReferenceException when trying to set registry permissions with C#

3 Answers3