|If you have already uninstalled other antivirus software, then you can simply go to the website www.norton.com/downloads and download the norton program and get it activated with the product key.|
You can also go to www.nortonaccount.com and sign in with the email address and password and if you dont know what the password is then there is also an option for recovering the password.
When you get an access to norton account, you can view the download button on the left and which you can use to download and install the norton program. Also you will get the option to renew, update information, view product key, etc.
If facing any issue can reply to this post..