UnauthorizedAccessException in ComRegisterFunction when accessing registry on Win 7 64

Question

I have a [ComRegisterFunction] that I am using to register a BHO Internet explorer extension. During registration on 64-bit windows 7 machines, a UnauthorizedAccessException is thrown on the call to subKey.SetValue("NoExplorer", 1).

The registry appears to have BHO's located @ \HKLM\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\explorer\Browser Helper Objects, however, I get them same exception when trying to register there. Any Help would be appreciated.

[ComRegisterFunction]
public static void RegisterBho(Type type) {  
    string BhoKeyName= "Software\\Microsoft\\Windows\\CurrentVersion\\Explorer\\Browser Helper Objects";

    RegistryKey registryKey = Registry.LocalMachine.OpenSubKey(BhoKeyName, true) ?? 
                              Registry.LocalMachine.CreateSubKey(BhoKeyName);

    if(registryKey == null) throw new ApplicationException("Unable to register Bho");

    registryKey.Flush();
    string guid = type.GUID.ToString("B");

    RegistryKey subKey = registryKey.OpenSubKey(guid) ?? registryKey.CreateSubKey(guid);

 if (subKey == null) throw new ApplicationException("Unable to register Bho");

 subKey.SetValue("NoExplorer", 1);
    registryKey.Close();
 subKey.Close();

}

Answer 1

Figured it out. I had to add the following to make it work. Not sure why it worked in other versions of the OS

RegistrySecurity rs = new RegistrySecurity();

rs.AddAccessRule(new RegistryAccessRule(user,
            RegistryRights.FullControl,
            InheritanceFlags.ObjectInherit,
            PropagationFlags.InheritOnly,
            AccessControlType.Allow));

RegistryKey subKey = registryKey.OpenSubKey(guid) ??    registryKey.CreateSubKey(guid, RegistryKeyPermissionCheck.Default, rs);

Answer 2

You need to run with administrative privileges.