diff --git a/3-socket-io/1-basic/package.json b/3-socket-io/1-basic/package.json
old mode 100755
new mode 100644
index acad99f..c39000b
--- a/3-socket-io/1-basic/package.json
+++ b/3-socket-io/1-basic/package.json
@@ -4,6 +4,6 @@
   "description": "my first socket.io app",
   "dependencies": {
     "express": "4.10.2",
-    "socket.io": "1.2.0"
+    "socket.io": "2.5.0"
   }
 }
\ No newline at end of file