Macbook pro certain keys keyboard not working, same result on internal AND external keyboard

Egghebrecht wrote:

Hello

My wife has a macbook PRO. Today she tried started it up and tried to log in using the password. The laptop didn't accept her password, when looking at the dots appearing when tying the password we noticed that certain keys didn't register and that the H key even worked as 'backspace'. Weird issue but we tried to circumvent it by connecting an external keyboard to the macbook. So we connected on of my keyboards and tried, and it gave the exact same result. Same buttons had the same result. The A didn't register, the H also worked as backspace etc. To make sure we tried the keyboard I am now typing this post on from my IMAC, same result.

Anyone have an idea what could be the cause here? Both the internal AND multiple external keyboards getting the exact same result is mighty odd.

Note: macbook PRO older model (don't know exactly which but 5 years ish old?) fully updated

We are locked at the login screen

Yes I have tried changing the keyboard settings in the top right corner, doesn't do much

Internal and external would suggest third party interference

If you are locked at the login screen then how do you make changes to keyboard settings...(?)

To trouble shoot further you can:

—Test issue in another user (or guest user) account Set up users, guests, and groups on Mac - Apple Support

This will tell you if it a universal issue or isolated to your user/admin account. 

—SafeBoot How to use safe mode on your Mac - Apple Support will sort many anomalies

Takes a bit longer to get to the login screen, does a quick disk repair before it fully boots up, and certain system caches get cleared and rebuilt, including dynamic loader cache, font cache, etc.

Login and test. Reboot as normal and test. Caches get rebuilt automatically.

In Safe mode third party system modifications and system accelerations are disabled, it removes malware, etc impacting the smooth operation, however a reboot will put it back to normal mode.

This test will tell you if third party interference; extensions etc are not loaded in safe boot mode.