Startup Repair cannot repair this computer automatically(No OS files found on disc)

Hi,

I have a problem with my HP Pavilion MS228UK. When I power it on, it runs Startup Repair and then gives me the mesage 'Startup Repair cannot repair this computer automatically'. In the details all the tests were completed successfully with error codes '0x0' except the last one which gave 'error code 0x490' with the message 'No OS files found on disc'. I ran the memory diagnostic tool which found no faults. I have tried to boot system recovery using F11 but that is not working either.

All help appreciated
Thanks