Did you run a full scan using malwarebytes on your PC in safe mode? If not, try that next. You didn't say which antivirus you are using and whether or not you have run a scan with your antivirus. If you did, was anything found by the AV?
Check that 'use a proxy server' is not ticked in Lan settings . Internet Explorer, tools, internet options, connections, Lan settings. Download Rkill from here. If it won't let you, try downloading in safe mode with networking. Stay in safe mode and run Rkill. Now run Malwarebytes antimalware and see if it picks it up.