>>Using VFP 6.0, service pack 3, looking for a technique or utility that will prevent a user from starting another instance of an app that is already running.
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>>Surely, someone has worked out a good reliable technique for this. Can anyone help?
>
>Look at the Windows API section; the sample for CreateEvent()( demonstrates a way to implement a single-instance application with minimal code.

Excellent! Thanks a lot.