diff --git a/AppHarbor.Net/AppHarborApi.cs b/AppHarbor.Net/AppHarborApi.cs
index 6951d3e..9b57032 100644
--- a/AppHarbor.Net/AppHarborApi.cs
+++ b/AppHarbor.Net/AppHarborApi.cs
@@ -108,20 +108,20 @@ internal AppHarborApi(AuthInfo authInfo, RestClient restClient)
 
         private static long ExtractLongID(string url)
         {
-            if (url == null)
-                throw new ArgumentNullException("url");
+            if (url == null)
+                return 0L;
 
             return Convert.ToInt64(ExtractID(url));
         }
 
         private static string ExtractID(string url)
-        {
-            if (url == null)
-                throw new ArgumentNullException("url");
+        {
+            if (url == null)
+                return string.Empty;
 
             return url.Split('/').Last();
-        }
-
+        }         
+ 
         private T ExecuteGet<T>(RestRequest request)
             where T : new()
         {