Hmmm. I never use that trigger with my barcode scanning.
Ron Smith, MD, 'The Pediatric Guide For Parents'
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Forever And A Day For Laura Michelle
That trigger is not used for scanning (although I may have implied that it was). I use the OnObjectKeystroke on several of my layouts for keyboard navigation within the layout as an alternative to using the mouse.
One clever solution I've seen for this (donated by Jeremy Bante) is to use an OnTimer Script to delay execution of your script. You use the OnObjectKeystroke to install the OnTimer script. If the OnTimer script times out, then the action proceeds. But each keystroke resets the timer, thus preventing FileMaker from getting hung up trying to execute the script, which may cause the "missing character" issue you're seeing.