NDIS test failed on MiniportHalt

[Paul Simon]

In the MiniprotHalt routin, I have to cancel timer queue
which I have set with NdisSetTimer and NdisInitializeTimer
at Miniport InitializeHandler. When I called *NdisMCancelTimer*,
I got an assertion failed.

*** Assertion failed: ((Timer)->Header.Type == TimerNotificationObject)
|| ((Timer)->Header.Type == TimerSynchronizationObject)
*** Source File: D:\nt\private\ntos\ke\timerobj.c, line 186

The code
VOID MPHalt(
IN NDIS_HANDLE MiniportAdapterContext)
{
PMP_ADAPTER Adapter = (PMP_ADAPTER) MiniportAdapterContext;
....
// Cancel pending timers
NdisMCancelTimer(&Adapter->Timer, &Cancelled);
....
}

Could you give me any suggestions or clues, thank in advance.