I downloaded and registered with Avast some months ago.
Following a recent hard drive failure I've had to download the free version again. I've also re-registered giving the same details as my original registration but have *not* received an email with registration number from Alwil.
What happens now as regards the registration process please?
You can use the old registration key if you still have it.
Are you sure that your ISP or your email client do not filter that email?
Do you have a spam killer?
Anyway, if you wait more than 3 hours, please, register again to receive a new number. Hope you succeed... Luck!