Not sure. The VFP Help file is not very helpful:

Record your recent actions while using Visual FoxPro and then call Microsoft Support.

Conflicting settings in the Device Manager for this port? Do you have another port you can try?

>I tried
>
>

fp = fopen('COM1',12)

>
>in VFP 7,8 & 9 beta and got an invalid seek offset error.
>
>Why ?