static extern bool SHSipPreference(IntPtr hwnd, SIPSTATE st);

Declare Function SHSipPreference Lib "aygshell.dll" (hwnd as IntPtr, st as Integer) As Bool

tells the system to ignore any pending down requests. That is, if SHSipPreference is called with the SIP_DOWN flag, the system sets a timer and after the timer fires, the input panel is lowered. However, if you call SIP_UNCHANGED before the timer fires, then the input panel will stay in its current location.

static extern bool SHSipPreference(IntPtr hwnd, SIPSTATE st);

     SHSipPreference(this.Handle, SIPSTATE.SIP_UP);

     SHSipPreference(this.Handle, SIPSTATE.SIP_FORCEDOWN);