System.NullReferenceException: Object reference not set to an instance of an object. at UserWebLink.UrlExists(String url) in c:\domains\1888implant\com\www\WebLink\UserWebLink.aspx.cs:line 316 at UserWebLink.Page_Load(Object sender, EventArgs e) in c:\domains\1888implant\com\www\WebLink\UserWebLink.aspx.cs:line 91