Windows 7 has context menu entries that can pin apps/documents/etc to either the Start Menu or to the Task Bar. I tracked down the CLSIDs for these items because I wanted a button in Opus to do these tasks so I can keep my context menu tidy. But when I add the following to a button:
FileType CONTEXTMENU (90AA3A4E-1CBA-4233-B8BB-535773D48449) CONTEXTFORCE
...and exit customize mode, the button disappears. Is it not possible to use this command in a button? Must it be used in a context menu?
Hrmm, it doesn't work in the context menu either...
In regedit, these two context menu items are showing up differently - they list their CLSID as the name, and the name as the data. Perhaps it this is why it's not working?
FileType CONTEXTMENU only really works in context menus. On toolbars it'll usually turn into nothing as the context menu cannot be built without knowing which files are selected and the toolbar doesn't know that until a button is clicked.
You can usually use ContextMenu SHOWCMDS to get a list of available context menu commands for a particular (type of) file, and then use ContextMenu VERB="xyz" to create a button which runs one of those commands.
However, there's a problem with the pin-to context menu items. They've been flagged as "extended" and only appear when shift is held down, but the ContextMenu SHOWCMDS/VERBS stuff doesn't support such commands at the moment. I've filed a feature request.
FWIW, at least on Win7 beta (I've not checked on the RC) there only seems to be an item for pin-to-start menu. I can't see anything in the context menu to pin things to the taskbar. Have to drag things on to the taskbar for that, as far as I can tell. Maybe it's changed in the RC, though.
Edit: Corrected the SHOWCMDS/VERB things. Before I had them as arguments to the FileType command but they're arguments to the separate ContextMenu command. (Not to be confused with the FileType CONTEXTMENU command+argument!)
I see. Thanks for the info! I never used explorer in Windows 7 so I didn't realize it had an 'extended' context menu. But they show up with Shift in Opus, so I suppose that's good enough. I guess I don't use them too often anyway.
Thanks again leo. You always seem to have the answer 
By the way, "pin to taskbar" is indeed present in the context menu in RC1...