comprei ontem o avast, porém, aparece um trojan do mcafee que não consigo desinstalar (vírus, com certeza). quando passo o avast, diz que não tem vírus na minha máquina
Did you have McAfee antivirus before using Avast?
If true, did you fully uninstall McAfee first before installing Avast.
If Avast finds McAfee files on your machine, it may likely consider them hostile.
Otherwise, can you post a screenshot of the AcAfee trojan indication, so we can see what you can see.
Note. I am not an Avast Team member, just another user.