Windows 8 isn't available for download

Just downloaded the Windows 8 Upgrade Assistant and only got the following message:

"Windows 8 isn't available for download", "Sorry, Windows 8 isn't available for online purchase in the country/region you're in."

I which region is then a download available?

I see you are running the wizard in Windows 8. Try running the wizard in compatibility mode (say Windows XP SP3).

You can find a list of the countries and regions included in the terms and conditions of the promotion: http://windows.microsoft.com/en-US/windows-8/terms-conditions

While you might be able to trick it into doing the upgrade, you really shouldn't...

Previews are not meant to be used by end customers (you can, but stability isn't guaranteed) and thus will not provide upgrade paths like those for end customers. It doesn't even make sense to introduce an upgrade path from a preview version to the full version. If they were to introduce an upgrade path for this, they would have to deal with a lot of fixes to corruption that was introduced by using the previews, which is one of the main reasons the upgrade path isn't even considered.

If you care for your data and not run into corruption or a buggy OS some time later, install it clean.

Check your system Time and Time zone. Check your IP address Geo Location. I think both of these didn't match.