opening/creating account

I have been obliged to re-install Windows and found it necessary to install Avast again. I noticed that I am not connected with any account, so I tried to register. My e-mail address is recognised, but I could not remember my password, so I tried to change it. I was sent an e-mail with a link, but when I clicked it I received the message ‘page not found’. I have tried this three times now, and am about to give up. It would certainly be easier not to bother with an account, however I shall try one last time to find a solution using this forum. Can anyone help?