Once again Problems with SerialPort class

Hi,

we were thinking (hoping) that with SerialPort we get a class solving the problems with the Serial Communications on PocketPCs.
But instead it works worse than our own implementation via PInvoke.

On thing I allready showed there:http://forums.microsoft.com/msdn/ShowPost.aspx?PostID=9794

Now we got a new one!
On an IPAQ we have a bluetooth barcode reader. The serial port for BT is Com8 in this case.
With our handmade Serial it is no problem to get strings form the BCR.
When I use SerialPort an try to open Com8 (no Data from the BCR - just open) I get an "IOException" stating the following:

StackTrace "at SerialStream.WinIOError()\r\nat SerialStream.WinIOError()\r\nat SerialStream.CheckResult()\r\nat SerialStream.SetBufferSizes()\r\nat SerialPort.Open()\r\nat Form1.btnOpen_Click()\r\nat Control.OnClick()\r\nat Button.OnClick()\r\nat ButtonBase.WnProc()\r\nat Control._InternalWnProc()\r\nat EVL.EnterMainLoop()\r\nat Application.Run()\r\nat Program.Main()\r\n" string

HRESULT: -2146232800

So whats the problem here? We open the port as any other one and it works.
Or in other words.
With our SerialClass we read GPS data from Com1 - it works.
With our SerialClass we read Barcode data from Com8 - it works.

We use SerialPort to read GPS data from Com1 - it works.
We use SerialPort to read barcode from Com8 it fails.

In both cases we use the exact same settings (excpet the portnumber) but SerialPort has a problem.
Any suggestions what could cause that error?

Cheers

Manfred

[1651 byte] By [ManniAT] at [2008-1-27]