>Williams,
>Managed to resolve the problem.
>We switched the card to a more expensive and better known brand (Advantech) and the problems disappeared!
>Guess its the hardware at fault this time.
>I even managed to open all 4 ports at the same time with no problems with this new card.
>The card comes with drivers for Windows but works thru mscomm32 rather than its own API.
>Thanks
>Yau
Yau - that is so cool !!! Cheap hardware for serial comms that kinda matches the 16550 FIFO UART specs is a royal PITA. Spend your money wisely and move on.

mondo regards [Bill]