Letter not working on my keyboard

Follow these steps, testing after each step:

• Software Update.
• Try Safe Mode.
• Use Apple Diagnostics to test your Mac.

If that didn’t work, then I recommend service.

Service Checklist:

• Mac service pricing.
• Check AppleCare Coverage.
• Get your Mac ready for service.

Click ▶︎ Start a Service Request. ⚛️

Need more help?

• Call Apple Support at 1-800-APLCARE. 📞
• International Support. 🌐
• Contact Apple Support. 📝
• Chat using Messages. 💬

Click ▶︎ Check Repair Status. 🔧

Did you try Safe Mode as already suggested? What was the result? Did the key work in Safe Moder or not?

It's extremely unlikely that a key would fail due to a software update.

Try an external keyboard - does the "n" key work?

Try the Keyboard Viewer: does clicking the "n" key in the Keyboard Viewer produce the letter n?

If the two tests above produce positive results, as I expect they will, then it almost certain it is a physical keyboard issue. Maybe some debris got under the key, or something.

One other simple test you can do is logging in to a new user account, or the guest account, and seeing if the "n" key works there.

If it does work, then that would point to some software issue, specifically on your normal account, and again not with the OS itself, but some third party software.

In my original reply, I suggested checking your AppleCare coverage in the event that you might need a service visit.

I hope you have coverage and good luck with your Genius Bar visit. 😉

You’re welcome! 😉

You’re welcome and good luck! 😉