Maybe you have a timer (and associated code) in your application?
I experience the same problem and I think it's related to that fact.



>From time to time, the menu item "Set Next Statement" is disabled in the debugger. I cannot see any pattern of circumstances to describe when this happens.
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>When it does happen, I can't get it to be enabled no matter what statement I try to set as the next statement -- even if it's the one immediately before or the one immediately after. Furthermore, if I Cancel and start over again, getting the same error at the same place (or stopping at "Set Step On"), it may well be enabled the second time.
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>Does anybody have any experience and/or specific information about this, or is this just yet another VFP gremlin to be endured?
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>Thanks,