Vista Home Premium suddenly reports Windows Not Genuine

[SteveM001]

This happened suddenly a week or two ago.. after having this laptop for 4 years. Tried running Malwarebytes, Antivirus thinking it could be a virus. Am having no luck getting rid of this erroneous display. Can it be fixed without reinstalling OS (Which was bundled with machine and therefore would be years out of date? Thank you for any help or advise that will help to clear up this error. -Steve

 

[hopgop1]

When it asks you to input a product key you can type in the key on the underside of the laptop on the Vista sticker.