Macbook pro return key acting weird

Troubleshooting a. Keyboard Key:

Try A. and B., If no success, then proceed to step C.

Deleting and Selecting Multiple Massages:

A. Try Safe Mode:

While in Safe Mode, try using this browser. In Safe Mode, login items do not run, and corrupt system files(i.e. caches) are intentionally reset as a way to fix issues.

1. Boot: in to Safe Mode: [Hold Down: shift key upon boot].
2. Log in: as same user
3. Try: this once more
4. Restart the Mac Normally
5. Try: this once more

B. Single-Out this User:

For troubleshooting purposes, try a new Administrator user, seeing if you do not get this occur while in it. Trash this user you've just created, once done. If you don't get the error, then it is only issue with the current user. If not, then it is an issue with the entire Mac, in which case you should reinstall the macOS. See below...

C. Reinstall the macOS:

Nothing would be deleted. It's just that items that have become corrupted or deleted, would be replaced or reinstalled back to where they should be. Go Here: How to reinstall macOS from macOS Recovery - Apple Support. Important: Be certain to create a backup of your Mac prior to performing the reinstall. That way, you can have something to restore from the Mac from, should anything go wrong with the reinstall. Once reinstalled, try this once more, seeing if you still get this error.

anna-runa Said:

"[...]the viewer acts as if I'm pressing Command + Return at the same time. Could this be the problem - my macbook 'thinks' I'm pressing a combination of keys when I'm pressing just one?[...]"

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Thank you for the screenshot.

External Keyboard:

If the reinstall didn't fix it, then it seems to be a hardware error. What happens when you place an external Mac keyboard in there? See if this screen still pops up. Ask a friend if you may try their keyboard, if you don't have one, yourself.

If no success with an external keyboard...

See About Getting your Mac Serviced...

Contact Apple, and setup a Genius Bar Appointment or see an AASP (Apple Authorized Service Provider) in your local area.

A. Contact Apple Support:

Contact Apple, and set up a Genius Bar Appointment at your local Apple Store.

• Contact Us - Choose Locations
• Proceed from there as Necessary
• Why the Wait: Phone calls are taking a bit to go through at the moment, due to lots of calls. With the Coronavirus Pandemic, many are at home at the moment, with much time on their hands to contact Apple. So, just stay on the line, and you will get through :)

And/Or...

B. Contact an AASP: 

1. Go Here: Find Locations - Apple Authorized Reseller
2. Click: Service & Support
3. Enter: your location information
4. See: if there is an AASP nearby
5. Contact: an AASP that shows up, and find out more about the services that they offer to replace the Mac's screen

Try an external keyboard. If that works ok, your problem is almost certainly hardware and not software.

I doubt that software settings are involved, but here is reference:

When Keys Don't Behave Correctly - Apple Community

anna-runa wrote:

My Macbook pro keyboard works great except for the return key. It's clickable and responsive in some situations, that's why i think it's either a software issue or some settings are off, not a hardware issue.

Maybe, an advice here might help you, if you've some settings problem.

Or, this might help you, if you have a hardware problem, that is, the key is simply malfunctioning.

One key combining with another like that normally indicates a hardware problem.