I have noticed that process named gdnUS2218.exe is trying to access internet. Of course I denied him access but he was constantly trying. I ran full virus scan and it reported some Trojan horse and said it removed them. But after some time this process tried to access internet again. I ran virus scan again, but this time antivirus told me he is unable to clean the virus. What should I do?
Restart the computer and boot in safe mode. This will prevent many processes to start including your Trojan. Then in a safe mode start antivirus scan and antivirus software will be able to clean the infection. Beside antivirus download and install antispyware tool and CCleaner. Run this tools in safe mode also. After this procedure Trojan will be definitely removed for good from your system.