diff --git a/src/main/main.ts b/src/main/main.ts
index 024fef4b6..e9b7267e5 100644
--- a/src/main/main.ts
+++ b/src/main/main.ts
@@ -109,7 +109,7 @@ const createWindow = async () => {
   mainWindow.loadURL(resolveHtmlPath("index.html")).catch(log.error);
 
   mainWindow.on("ready-to-show", () => {
-    Preconditions.checkExists(mainWindow);
+    Preconditions.checkExists(mainWindow, '"mainWindow" is not defined');
 
     didFinishLoad = true;