>Probably something obvious, but I'm not getting it.
>
>I have defined a column class and its header class in a prg file. In that class definition, I set the HeaderClass property, and the HeaderClassLibrary property to the full path to the prg file.
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>In the form designer, I instance a grid on a page and set the grid's MemberClass property to the column class in the prg file, and the MemberClassLibrary property to the full path to the prg file.
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>When I run the form, the grid works normally.
>
>Back in the form designer, I select the grid > right click > copy, go to a different page, and right click and paste. I get an error message saying that the header class definition is not found. If I look at the properties of the columns in the grid, I can see that the HeaderClass and HeaderClassLibrary are correct.
>
>Why does this happen? Is there a way to copy a grid set up in the form designer to another container?

Few things to try:
- change the path to the header's prg to be a relative one (the one in the vcx is relative internally, no matter how it looks in the PEM window)
- add the folder with these prgs to the path while you copy
- set procedure to all the prgs where your classes are defined while you copy

HTH - I've found that some intellisense things work (which usually wouldn't) when you have set procedure to the prgs where your definitions are. May help in your case.