Yes indeed, the LVM_DELETEALLITEMS is the best, most efficient and fastest way you can get: it's the pure Win32 API! (and we all love that thing don't we?)
I suggest you to try fix my code (make use of that Debug::Trace function!) or try roflmao456's code. The reason why my function uses a call to SendMessage instead of using PlusWnd::SendControlMessage is so that I don't have to pass that whole PlusWnd object to the function, but roflmao's code will do just the same thing and may turn out even more interesting if you only want to use the list cleaning one or two times and you don't really need a separate function for it.
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