Hello! I have a following problem. I have a page with a ModalPopupExtender. This extender is used to show a user control which contains a user control with a GridView on it. Now the problem is that when I get the UniqueID of the GridView's parent control it looks like: "ctl00$cphContent$hierarchyEditor$gvAvailableLevels" which is perfectly fine. But the UniqueID of the GridView inside is just: "gvAvailableLevels$gv". Why is that? As a consequence I cannot post back correctly to select a row. I would appreciate any suggestions.