There're many ways to prevent the second instance of application from running. The simplest one and least reliable is to check if application with the same Caption is already running http://www.levelextreme.com/Report.aspx?Session=34506835374E666E5A6A633D20734F734A62465236742F6839614C73707661696D6D4B4C393456646B666C5048
The better way is to use Windows Events as shown in http://www.levelextreme.com/Report.aspx?Session=546A76416F5931775343303D205574476238364F365147393046596757787A655075536E68372F4F43505A452B

For externall applications check http://www.berezniker.com/content/pages/visual-foxpro/check-if-exe-running-and-optionally-terminate-it

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>Occasionally, user has already launch the EXE and will launch another copy
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>I want to be able to prevent a user from opening more than one instance of my app EXE.
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>Please advise if there is an easy way to detect an VFP EXE has been launched and prevent user from starting the app the 2nd time.
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