I just tried to renew nod32 antivirus on sons computer. Received conformation, username and password to download. Problem is when I enter the supplied username and password in the pop up authentication window it immediately closes and pops up a new authentication window with a different username already filled in. I have purchased nod 32 for 3 different computers in the home individually. After attempting 3 times to re-enter user name/password (cut and paste) an error message tells me that either I am enterting the wrong username password or the system doesn't know how to allow authentication. Thanks for your help.