From my personal and technical experience with ecus design,
communications protocols and software writing....

9 out of 10 problems arising from USB/serial converters IS the software
application itself and NOT the interface and/or its drivers.

Its all too easy for the application providers to blame the interface drivers
and hardware rather than sort there own problems as its easy to do so
and they also forget that not all compatiable PCs are truly "compatiable"



As I have said on another thread I recently have rewritten my ecu
software for the 32 bit windows platform and too had these issues of
trying to get various interfaces to work reliably with my ecu.

In the end I took advice from another software company who let me in
on a few trade secrets which i incorporated in to my software.
From that point on, ALL interfaces I had tried previously that did not
work started to work perfectly.




Hope you sort your problems