I have bought a new laptop with Windows 7 and I would like to ask if Avast Free disables Windows Defender automatically during installation. Should I disable Windows Defender manually before installing Avast? Or maybe there is no problem running Avast and Windows Defender together?
Thanks.
There is no problem in running Windows Defender (WD) along with Avast, but to be honest with you, there really is no need to run WD at all since Avast is so much stronger and the updates are more frequent.
What is your OS?
Do you have any other security programs on your machine: on-demand or resident?
My operating system is Windows 7 Home Premium and I am going to install only Avast Free.
Good…save your memory and don’t bother with WD. However you may want to install Malwarebytes Anti-malware (MBAM) as either an on-demand or resident scanner. It does not conflict with Avast and works differently from an AV. You can download it from here: http://www.malwarebytes.org/.
Only on W8. 
I have bought a new laptop with Windows 7as Safe surf already asked......was it deliverd with a preinstalled AV from the factory?
It has a trial of Mcafee, but I will uninstall it.
it is recomended that you run a removal tool to clear any leftover files that may conflict
run and reboot - http://singularlabs.com/uninstallers/security-software/