Have bought Avast 1 year 3 computers. Installed on one computer. Don’t know how to install to the other two. Is there just one activation code for all three? Do I have to download the code for each computer? Detailed instructions would be welcome. Thanks for any help.
Yes there is one activation code for the multi-system license.
Copy the license file to your other systems and do the same there as for the first installation.
Not sure what you mean by download the code for each computer, if you mean license then the above applies.
Detailed instructions in FAQ section http://www.avast.com/faq.php?q=2014#searchForm