03-02-2017 09:41 PM
Welcome to Lenovo Community! And happy to have you here.
As I understand that you are facing issue related to Keyboard in your L450.
You can try checking in Safe Mode whether keys are working in that mode or not.
Also check with this online site to isolate between hardware & software issue.
And if system is still under warranty you can contact Lenovo Support , they will arrange for Keyboard replacement.
I hope the above information helped you.
Please feel free to post in Lenovo Community Forums if you have any further queries!
Tap that Kudos button if I helped.
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