Question about Virtual Serial

I followed the step of Eliyas Yakub How to Make a Virtual Port.

Frome Step 1 to Step 3 I was success, but the step 4:

Step4

Once the steps above have been completed, the bus driver
can now start receiving IRPs from any application such as HyperTerminal.
For a list of all the IOCTL IRPs that have to be handled, refer to
the "SerialIoControl " function in the “serial” sample in the DDK. By
implementing the handler code for these IRPs, the virtual com port should
now be fully
functional.

Yes, I can use HyperTerminal to open the COMx that I had installed, but I
can not handled the Serial IOCTL IRPs,

I don’t know what happened. I added the “SerialIoControl” function in the
Bus_IoCtl(busenum.c)£¬

if (!fdoData->IsFDO)
{

status = SerialIoControl(DeviceObject,Irp);

}

I can’t see any DebugCode of IOCTL IRPs in the DebugView, and the
HyperTerminal said “Unable to open COMx.
Please check your port settings”

please reply me…

Best Regards…
Daniel Xu