diff --git a/Core/Requests/ServiceRequestBase.cs b/Core/Requests/ServiceRequestBase.cs
index 7eec18a0..882e0dad 100644
--- a/Core/Requests/ServiceRequestBase.cs
+++ b/Core/Requests/ServiceRequestBase.cs
@@ -108,6 +108,10 @@ protected static Stream GetResponseStream(IEwsHttpWebResponse response, int read
 
         private static Stream WrapStream(Stream responseStream, string contentEncoding)
         {
+            if (string.IsNullOrEmpty(contentEncoding))
+            {
+                return responseStream;
+            }
             if (contentEncoding.ToLowerInvariant().Contains("gzip"))
             {
                 return new GZipStream(responseStream, CompressionMode.Decompress);
@@ -933,4 +937,4 @@ private void ReadXmlDeclaration(EwsServiceXmlReader reader)
 
         #endregion
     }
-}
\ No newline at end of file
+}