diff --git a/src/ts/@overflow/commons/websocket/protocol/ProtocolError.ts b/src/ts/@overflow/commons/websocket/protocol/ProtocolError.ts
index ea0bf4e..c4ca8e3 100644
--- a/src/ts/@overflow/commons/websocket/protocol/ProtocolError.ts
+++ b/src/ts/@overflow/commons/websocket/protocol/ProtocolError.ts
@@ -42,6 +42,9 @@ export class ProtocolError {
   }
 
   public static convert(error: ProtocolError): ProtocolError {
+    if (undefined === error) {
+      return undefined;
+    }
     const code = error.code;
     if (undefined === code) {
       throw new Error(`Error must include Code`);
diff --git a/src/ts/@overflow/commons/websocket/protocol/Response.ts b/src/ts/@overflow/commons/websocket/protocol/Response.ts
index a162fcc..3981dcb 100644
--- a/src/ts/@overflow/commons/websocket/protocol/Response.ts
+++ b/src/ts/@overflow/commons/websocket/protocol/Response.ts
@@ -43,7 +43,9 @@ export class Response<ID> extends Header {
     let res = new Response(id);
     res.Protocol = response.protocol;
     res.result = response.result;
-    res.error = ProtocolError.convert(response.error);
+    if (undefined !== response.error) {
+      res.error = ProtocolError.convert(response.error);
+    }
     return res;
   }