If it's out of warranty, repair won't be free.
Select a repair shop that can do it quickly, or that can provide you with a laptop to use for how long it takes to repair.
But first I would try:
1. Does the keyboard work enough to get you in the BIOS (press the magic key) and does it work there?
2. Can you boot from a Linux disk and does it work then?
If both are yes, it might be a driver or setting issue in Windows. Then go back to factory conditions the way the user manual tells you or from the recovery disks you made (you did make them, didn't you?)
Kees
I have had my Sony Vaio (SVF152C29M) for just over a year now, I have not had any problems until last week when the keyboard started playing up. Some of the keys just would not type whilst others would get stuff and would repetively type into every text box until the laptop was shutdown/restarted, therefore I used either the touchscreen or a USB keyboard that I have used for years and have used before with this laptop. Yesterday when turned on, upon trying to sign into my user account, the keyboard again would not work but no keys would work, the USB keyboard would not work either and the touchscreen would responded to clicks but the touchscreen keyboard would not type either. I now am not even signed into my computer so it is currently completely unusable and I cannot even download any software to fix the problem. I have just arrived at university in London yesterday so there is no other laptop/computer I can use, I'm stuck with my phone! Please help me!!

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