diff --git a/src/main/java/com/corundumstudio/socketio/handler/EncoderHandler.java b/src/main/java/com/corundumstudio/socketio/handler/EncoderHandler.java
index c101d60..0637337 100644
--- a/src/main/java/com/corundumstudio/socketio/handler/EncoderHandler.java
+++ b/src/main/java/com/corundumstudio/socketio/handler/EncoderHandler.java
@@ -169,6 +169,7 @@ public class EncoderHandler extends ChannelOutboundHandlerAdapter {
 
         if (configuration.getOrigin() != null) {
             HttpHeaders.addHeader(res, ACCESS_CONTROL_ALLOW_ORIGIN, configuration.getOrigin());
+            HttpHeaders.addHeader(res, ACCESS_CONTROL_ALLOW_CREDENTIALS, Boolean.TRUE);
         } else {
             String origin = channel.attr(ORIGIN).get();
             if (origin != null) {
@@ -176,6 +177,7 @@ public class EncoderHandler extends ChannelOutboundHandlerAdapter {
                 HttpHeaders.addHeader(res, ACCESS_CONTROL_ALLOW_CREDENTIALS, Boolean.TRUE);
             } else {
                 HttpHeaders.addHeader(res, ACCESS_CONTROL_ALLOW_ORIGIN, "*");
+                HttpHeaders.addHeader(res, ACCESS_CONTROL_ALLOW_CREDENTIALS, Boolean.TRUE);
             }
         }
     }