>>>Raphael,
>>>VFP9:
>>>Maximum # of characters per macro substituted line 8,192
>>>
>>>But if this is an issue, why EditBox outside the grid works?
>>
>> What happens if you run the function via a cmdButton to a form value and then assign the controlSource for the grid column to that form value?
>
>The same: String is too long to fit, when column gets focus.

hmm, could it be that a grid column won't support more than 255 chars in width for any editBox? How many rows is the editBox? maybe more rows would help.