Thanks for that Al,

Sorry for the delay in replying ..

I swithched the progam to using asynchronous calls and all is now OK. Whwn using the synchronous calls the PC was not accessing the hard disk at all just 'locking' the processor up to the VFP app. I had tried messing around with sys(3050) setting but this made no difference to this problem.

Anyway, thanks again.

Alec.