LICENCE EXPIRED AV. GOT THE KEY

I get LIC Expired message. I have re-registered, GOT THE KEY BUT HOW DO I APPLY THIS KEY to it ? XP AAV.
Do I have to re-install or is there a file that I need to run to renew the licence ?
Thanks for UR help.

Please don’t post multiple posts for the same question, it just causes duplication for those helping and your first post has been answered.

Sorry I am new but I don’t see it replied yet except you.
Sorry again.
Park.

Click the Profile button at the top of each page, here you can modify how you are informed about posts (receive an email). See the ‘Notifications and Email’ sections and ensure that you have the notifications enabled.

You can also use the Profile information to see what you have previously posted with links to those posts ‘Show the last posts of this person.’ Your other Topic http://forum.avast.com/index.php?topic=22218.msg184621#msg184621

Welcome to the forums.

Sorry but could someone who knows tell me how to apply the registration key to the already runing anti virus on XP.
I don’t see an obivious option.
I have setup notification as suggested.
Thanks.
Park.

View this tutorial Insert Registration Key - Video