No internet access after multiple virus removals


Jun 28, 2016
My girlfriend's laptop was infected with dozens of malware of a lot of kinds like Trojans, adware, droppers and some of them were even located in C://Windows/ so I installed avast and did multiple scans including boot time scan and they removed every malicious file on the system, but after the computer boots up there is no internet access, not in the browser nor other programs like Skype. Programs like avast safezone browser and teamviewer managed to get internet access, but it's very slow. I don't know what is restricting the internet access, I tried disabling the antivirus and firewall but still cannot access internet, but when i launch Google chrome or internet explorer it can access 2 pages or 3 and they are the startup pages which hijacked the browser, so I don't think the system is clean yet? I get many RunDLL errors and it's probably the malicious process causing them, and I get runtime error when trying to install some stuff like malwarebytes. Any help is appreciated.