When I use AXGridView in User control, I get this error "There was an error rendering control. Value cannot be null. Parameter name: Child". I went ahead and tested the User control in Visual studio, the aspx page was able to render the page with data in grid.
But, it does not load in Enterprise portal. The page becomes corrupt after adding this User control.
Request your suggestions!
More Details: Ax SP1 RU6 2009
Windows Server 2008 R2, 62 bit version
Visual Studio 2008 professional edition
Check this link..It should help...