I have a windows program written in vb6 that works fine in either xp sp2 or xp sp3, using the CDC virtual com demo in MQX with a 52259. However, when I try to use a similar program written in VB2005 in .NET, it doesnt work. The 52259 never sees any USB activity when the program sends data. The 52259 is showing up as a virtual com port correctly in device manager, and Im able to open the port in VB, but when I write to the port, nothing shows in in the 52259. Ive tried using a port sniffer, and it shows data being sent over the virtual com port but it never makes it to the 52259.
Ive tried replacing the xpsp3 usbser.sys driver with the one fron xp sp2, but it didnt help. Is there anyone else that has had this problem and figured out what is going on?