Recently I installed an antivirus which name is Avast.
After installing it, my webcam does not work.
But in the past, I could use it and I could easily take any picture and also record video.
What is the problem?
Avast is an antivirus program, so I do not think it is the one affecting your webcam.
But I suspect that when you installed it, it had a virus or other malware that came with it and it is the one that is probably stopping your webcam drivers from functioning properly.
My suggestion is that you uninstall it if possible and install a genuine and stronger antivirus like AVG which can trace that virus/malware/Trojan and remove it.
And for your safety, try as much as possible to avoid using second rate programs, or programs from sites that are not trusted from the internet since some of them come with viruses embedded.-that is if you may be using them.
