Add the guard on the wrapping content.

Mobile.Search.Web/Controllers/TemplateController.cs

@@ -171,7 +171,11 @@ namespace Mobile.Search.Web.Controllers
                         {
                             to_replace= String.Format("{{{{WrapAdvertiserUnsubscribeUrl('{0}')}}}}", m.Groups[1]);
                         }
-                        value = value.Replace(m.Groups[1].Value, to_replace);
+                        if(m.Groups[1].Value.Count()>0)
+                        {
+                            value = value.Replace(m.Groups[1].Value, to_replace);
+                        }
+                        
                     }
                     m = m.NextMatch();
 
@@ -208,7 +212,8 @@ namespace Mobile.Search.Web.Controllers
             catch (Exception x)
             {
                 Log.Error("Edit: Error " + x);
-                return View();
+                return Json(new { status = "Failed" });
+               
             }
         }