>I can't remember how this happens, and I'm sure I used to know.
>
>In a form, a textbox fires an "invalid date" message ONLY when run in development mode.
>When built into an executable, it just hangs infinitely when the 31st of June is entered.
>
>Yes, I know that 31/6/2004 is invalid, and so should the user (30 days have September, etc).
>But something is not triggering the message in runtime, different from development.
>SET DATE, SET SYSFORMATS, what is it?
If you use SET SYSFORMATS ON, the settings (for instance, DMY vs. MDY) will be read from the Control Panel; this can be different for different users.
To ensure consistent settings, you might either SET SYSFORMATS OFF, or ask the user to try with the same date format you use on the development, machine, for example, DD/MM/YYYY.
On the other hand, I think you ought to get the same error message for ANY invalid date. Perhaps you should check error handling.
Difference in opinions hath cost many millions of lives: for instance, whether flesh be bread, or bread be flesh; whether whistling be a vice or a virtue; whether it be better to kiss a post, or throw it into the fire... (from Gulliver's Travels)