diff --git a/scripts/postinstall.js b/scripts/postinstall.js
index 29b03df39..c7a8c79b0 100644
--- a/scripts/postinstall.js
+++ b/scripts/postinstall.js
@@ -90,9 +90,9 @@ npm('install', {cwd: './app', env: 'electron'}).then(() => {
 
     // if the user hasn't cloned the private mailsync module, download
     // the binary for their operating system that was shipped to S3.
-    // if (!fs.existsSync('./mailsync/build.sh')) {
-    //   console.log(`\n-- Downloading a compiled version of Mailspring mailsync --`)
-    //   downloadMailsync();
-    // }
+    if (!fs.existsSync('./mailsync/build.sh')) {
+      console.log(`\n-- Downloading a compiled version of Mailspring mailsync --`)
+      downloadMailsync();
+    }
   });
 });