diff --git a/proxy/nginx/conf.d/rocketchat.conf b/proxy/nginx/conf.d/rocketchat.conf
index 6dd2b3f..e148f0e 100644
--- a/proxy/nginx/conf.d/rocketchat.conf
+++ b/proxy/nginx/conf.d/rocketchat.conf
@@ -32,5 +32,5 @@ server {
 		# WebSocket support
     proxy_http_version 1.1;
     proxy_set_header Upgrade $http_upgrade;
-    proxy_set_header Connection "upgrade";
+    proxy_set_header Connection "Upgrade";
 }