When you open a RadNotification in a scrolled page in Edge, it will appear higher than expected or it might not appear at all depending on how much the page is scrolled. 

You can avoid the issue by placing the following script at the end of your page:

		<script type="text/javascript">
			Telerik.Web.UI.RadNotification.prototype._originalSetPopupValue = Telerik.Web.UI.RadNotification.prototype._setPopupVisible;
			Telerik.Web.UI.RadNotification.prototype._setPopupVisible = function(x, y) 
			{
				if (Telerik.Web.Browser.edge) {
					var offsetY = window.pageYOffset;
					var offsetX = window.pageXOffset;

					if (document.documentElement.scrollTop == 0 && document.body.scrollTop > 0)
						y += offsetY;
					if (document.documentElement.scrollLeft == 0 && document.body.scrollLeft > 0)
						x += offsetX;
				}
				this._originalSetPopupValue(x, y);
			}
		</script>