Enter key intermittently stops working on both my Macbook Pro's & external keyboard My Macbook Pro is 5 months old and I've started to get "enter" key failure on both my internal and external keyboards.
It works again when I restart the laptop. The fact that it's happening on both keyboards tells me that it's not a hardware issue per se.
I've cleaned both keyboards to make sure it wasn't due to a dirty underside of the keys.
Can anyone provide some guidance on this?
It's very interesting that the external keyboard and internal keyboard are having issues with the same key. One action I also recommend when hardware like keyboards, back lighting, ports, chargers aren't working is to reset the SMC (System Management Controller). 

In the meantime, let us know a little more information:


Is the external keyboard wired or bluetooth?
Is this issue only happening with the Enter key, and no other keys?
Does the keyboard issue occur randomly, or have you noticed a pattern (like during certain apps, or when logging in, etc.)?
Do you have Apple Care or any other warranty?