Website returns 404 error for www links

Link that works: http://ift.tt/2kg8uSp Links that doesn't work (404 error): http://ift.tt/2jWKgR9

The issue is that when I go to www.link it doesn't work, it gets a 404 error. How can I fix it? Do I change something in the DNS server where I bought the domain? (godaddy)

thank you