The best thing if you haven't already done it is download and install malwarebytes
http://www.malwarebytes.org/lp/lp4_r...Fe3JtAod4QUALw
It's probably the best free anti malware software you can find, after installing it run a full system scan and quarantine anything that comes up, repeat if needed and then from there if you have more issues it can be narrowed down.
You may have to do all this in the computers safe mode if you can't download from the malwarebytes site.