How do I troubleshoot my Express.js application?

I'm having issues with my Express.js app not responding. What should I check first?

First, check if your server is running. You can do this by looking at the terminal where you started your app.

The server is running, but I'm getting a 404 error when I try to access a route.

A 404 error usually means that the route is not defined. Double-check your route definitions in your app.

I see that I misspelled the route name. How can I fix it?

You can fix it by correcting the spelling in your route definition and then restarting your server.

Thanks! What if I encounter a database connection error next?

If you encounter a database connection error, check your database configuration and ensure the database server is running.