I'm not too technically minded so I'll explain this as best I can and hope somebody can help me out.
A few weeks ago my media player stopped working - it flashes onto the screen for a split second and then disappears or just doesn't respond at all. Also the HP Advisor isn't working properly and keeps saying "an error ocurred" links don't work on the help section so I went to the HP site to try to get help there. I opened one of these instant help chat boxes and a technician phoned me, said he could help etc mentioned a one off charge and it took me half an hour to find out how much etc. He had remote access to my laptop and was running scans that found several thousand problems and now I'm worried that he may have "planted" something in my pc. When I told him I couldn't pay what he was asking he finished the call pretty quick and left me to it.
How do I fix my problem and how do I found out if he left something malicious on my pc? I'm scared to do internet banking now :-(