Partnere has an HP running on windows 7, about 18 months old but having problems with po ups. Had the same myself (windows 8) last year but help from the brains trust on here all sorted, any advice please?.
+1 for Malwarebytes. Just be careful where you download it from. Their own website is www.malwarebytes.org. OH downloaded a dodgy version off one of those free download sites and it screwed his machine up completely.