NullReferenceException when trying to read a registry key with C#

Question

I'm trying to read and write to the same registry key. However I can't seem to access it. I've checked the path a million times and it's correct.

RegistryKey key = Registry.LocalMachine.OpenSubKey("HKEY_CLASSES_ROOT\\apart\\Shell\\Open\\Command");
MessageBox.Show(key.ToString());

Please also see if [Cannot access HKEY_CLASSES_ROOT\Installer on Windows Server 2008 Enterprise](http://stackoverflow.com/questions/9180563/cannot-access-hkey-classes-root-installer-on-windows-server-2008-enterprise) helps solve your issue (FYI all I did was Google `C# OpenSubKey returns null`) — tnw, Sep 22 '14 at 20:35

score 6 · Accepted Answer · answered Sep 22 '14 at 20:37

6

LocalMachine corresponds to HKEY_LOCAL_MACHINE.

ClassesRoot represents HKEY_CLASSES_ROOT.

Try

RegistryKey key = Registry.ClassesRoot.OpenSubKey("apart\\Shell\\Open\\Command");

answered Sep 22 '14 at 20:37

AlexD

score 1 · Answer 2 · answered Sep 22 '14 at 20:38

1

You might want to try the following:

RegistryKey key = Registry.ClassesRoot.OpenSubKey("apart\\Shell\\Open\\Command");
MessageBox.Show(key.ToString());

answered Sep 22 '14 at 20:38

asfaloth.arwen

2 Answers2