Help?! anyone? registration problems

Hello. I’ve recently purchased the free Avast 4.8, and received a registration code in e-mail. The problem is that whenever I enter the code (copy&paste) it says : Error: Invalid Registration Code. Can you help me with this issue?
Regards…

See the tutorial: http://www.avast.com/files/tutorials/insert_key.htm
Please take a look here: http://www.avast.com/eng/faq-invalid-license-number.html

Is your system date/time correct?
Are you sure you do not include the ‘last blank space’ in the paragraph while copying & pasting?

Also take a look here… http://forum.avast.com/index.php?topic=34661.msg290864#msg290864

You purchased the free version ???

Where did you do this as it is free, only the avast Pro version is a paid option.
So it may be possible that you have the victim of a fraudulent transaction, see http://www.avast.com/eng/fraudulent-sales-of-avast-products.html][url]http://www.avast.com/eng/fraudulent-sales-of-avast-products.html[/url].

That could be why you are getting the invalid key, but entirely depends on a) what version of avast you have Home or Pro and b) where you got it and where you paid ?