Cini mi se da sam nasao resenje - jos testiram - trebalo je deklarisati ovu funkciju:
Code:
[DllImport("shell32.dll", CharSet = CharSet.Auto, SetLastError = true)]
public static extern void SHChangeNotify(uint wEventId, uint uFlags, IntPtr dwItem1, IntPtr dwItem2);
const uint SHCNF_IDLIST = 0x0;
const uint SHCNE_ASSOCCHANGED = 0x08000000;
I onda posle promene asocijacija i dodavanja context itema u explorer-ov meni - izvrsiti ovo
Code:
SHChangeNotify(SHCNE_ASSOCCHANGED, SHCNF_IDLIST, IntPtr.Zero, IntPtr.Zero);