Can't register file associations.

[WhoMI7]

Getting this:

UnauthorizedAccessException

Access to the registry key 'HKEY_CLASSES_ROOT\PhotoViewer.FileAssoc.Tiff\shell\MediaInfo.NET' is denied.

System.UnauthorizedAccessException: Access to the registry key 'HKEY_CLASSES_ROOT\PhotoViewer.FileAssoc.Tiff\shell\MediaInfo.NET' is denied.
   at Microsoft.Win32.RegistryKey.Win32Error(Int32 errorCode, String str)
   at Microsoft.Win32.RegistryKey.CreateSubKeyInternal(String subkey, RegistryKeyPermissionCheck permissionCheck, Object registrySecurityObj, RegistryOptions registryOptions)
   at Microsoft.Win32.RegistryKey.CreateSubKey(String subkey, RegistryKeyPermissionCheck permissionCheck)
   at RegistryHelp.SetValue(String path, String name, Object value) in D:\Projects\CS\MediaInfo.NET\src\RegistryHelp.cs:line 11
   at MediaInfoNET.Program.Setup(Boolean install) in D:\Projects\CS\MediaInfo.NET\src\Program.cs:line 58
   at MediaInfoNET.Program.Main(String[] args) in D:\Projects\CS\MediaInfo.NET\src\Program.cs:line 18

Tried running mediainfo as admin too.