Plug in a PC USB Keyboard and see if the keys work on the USB keyboard.
If it does, it sounds like the usual keyboard failure. Keyboards run from 10 to 100 bucks and are a good introduction to minor PC repairs.
Since you reimaged the laptop I do not suspect settings or such. The test is quick and tells us what to do next.
Hi guys, first post in regards to issue I have !
Two days ago I had my computer in a public place and since some keys on the keyboard don’t work, ctrl.del.alt ; del ,esc, fn and number five, six and one . I reimage the computer and problem hasn’t resolved, and yesterday I push many keys at and pushed number one at the same time so then 1 is functioning again,i dont know which combination fixed though! ,I think may be some one disabled these keys, I have very strong antivirus so that is very unlikely for this to be virus or key failure ;as Number one is working again, anyone knows how to fix this? Is it possible for somebody to disable keys by a combination on the key board? Thank you in advance! I smashed and de-dust and other stuff as well!

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