Right Click in Windows Explorer

I have been trying to add context based right click in windows explorer for a file of extension L5X. I have tried HKEY_CLASSES_ROOT\l5xfile\Shell\convert\command and set the (Default) key value to the program I want to have open the file. (I want it to say "Convert" on the context menu) My first issue seems to be that in .NET (even when running elevated) I cannot change the Default key's value. My other issue is changing that Default key value doesn't do anything to the context menu. I would really prefer a no reboot required solution.

Also, I really need this to work on WinXP all the way up to Win7 (including Server 2003, 2008 and 2008R2). If I need to detect OS and do thi开发者_StackOverflow中文版ngs differently for different OSes, I will but I'm really stuck here.

PS, I tried the solution found here with no luck.

You need administrator rights to write to HKEY_CLASSES_ROOT, HKEY_CLASSES_ROOT is a merged view of HKEY_LOCAL_MACHINE\SOFTWARE\Classes and HKEY_CURRENT_USER\Software\Classes. If you want to install it for just the current user, write to HKEY_CURRENT_USER\Software\Classes

\l5xfile\Shell\convert\command might not be the correct path, when windows looks for context menu entries for a filetype, it first looks in HKEY_CLASSES_ROOT\.EXT, then uses the default value it finds there: HKEY_CLASSES_ROOT\%defaultvaluefrom.EXT%\Shell\*

XP added a new key HKEY_CLASSES_ROOT\SystemFileAssociations designed for non-primary actions where you don't care about the ProgId/Class (The l5xfile part)

MSDN documents all these registry paths and settings, see: File Types and Verbs and File Associations