Thank you both.

>Hi Naomi,
>
>The problem can be in child forms. The VFP save informations inherited conteiners objects from class in field PROPERTIES for row baseclass="FORM".
>
>0) backup child forms
>1) open child forms as table and drop all properties about inherited forms.
>2) modi child forms and add new column.
>
>MartinaJ
>
>>Hi everybody,
>>
>>I have the following heararchy of forms (classes)
>>
>>FormParent (with a grid)
>>
>>FormChild1
>>FormChild2
>>
>>I found that in both FormChild1 and FormChild2 the original grid was modified (one more column was added). I re-set the column number to the original number, created a grid as a separate class in the same library and added it to the parent form.
>>
>>Now, both forms are displayed correctly, but as soon as I press run button (from the forms in run-time) I see a dreadful Internal consistency error and then I can only send report to MS. Even more to that, at some point I managed to make this dialog to be non-closable (e.g. it was coming and coming again). Somehow I managed to kill it though (I recall Michel Fournier had the similar problem in the past too).
>>
>>Anyway, do you have ideas what to do to get rid of this error? I re-compiled the library in question.
>>
>>Thanks in advance.
>>
>>------------------------------------
>>UPDATE. Disregard. Found that one of the columns (newly added was bound to non-existing field).