921600 Baud Rate

[paul.knight@zeroavia.com]

I am getting this error:

when I try to do an OpenComConfig with any baud rate greater than 115200.

I can open the port using TeraTerm all the way up to 921600.

The code is nothing special 

iStatus = OpenComConfig(1,
"COM1",
921600,
0,
8,
1,
4096,
4096);

[paul.knight@zeroavia.com]

Not my code, LabWindows RS232 library can't.  I wrote code using the Windows SDK and it works fine.