I determined the minimum registry key permissions to actually let Now Playing for Live Messenger plugin do it's work... Make sure everything is working the way you want, before you continue. You cannot change the now playing option after enabling below minimum security settings. You will see crashes in unexptected ways if you change the now playing option after enabling below ; ) Find the registry object (see 1st post) which contains the entry "music plugin for windows live messenger". Right-click the object to Change Permissions... Click advanced. Remove all listed permissions. Disable the option Inerit permissions from above (I have to translate from Dutch... So English text will vary: ). Enable (by checking) the option to intherit permissions to reset below objects and enable inheritable permissions. When you press OK and answer Yes once or twice, everything is clean and nothing will work. Next, add two users to the permissions: Administrators and System. Give them the following set of permissions: DENY: everything, except for: Complete Control, Request Value, Index (inventarise?) subkeys, Report. ALLOW: Request value, index subkeys, report, make shortcut. If Administrators and System is as requested above, the Now Playing plug-in will work. Hower, when mediaplayer crashes again, the option still is disabled. How? I don't know yet. I'll repost if I continue this thing / find a solution. Still interested in feedback! Oh, and Peace! : P Devvie Nuis. PS: Administrators can be changed to the user-account you are using... Administrators probably is the easiest...