xml file updations

Question

Hi,
There is an error occur when editing datas in xml in Live site.The error is like as follows.Please help me to solve this problem

Source Error:

Line 132:            //}
Line 133:            //xnode["Email"].InnerText = txtemail.Text;
Line 134:            xDoc.Save(Server.MapPath(@"~/App_Data/XmlFolder/Events.xml"));
Line 135:            txtstrtdate.Text = string.Empty;
Line 136:            txtdate.Text = string.Empty;