I recently formatted my laptop which came with Vista preinstalled and installed Windows 7 on the primary partition. I've now installed Vista on a different partition, but it won't activate my valid product key. I've looked around on here and have seen similar issues being raised, but I don't have the telephonic activation option (only option I have is online activation). I am located in South Africa.

When I enter my product key from my sticker it says it is not valid, so I must either try to activate online again or buy a different product key. I have reinstalled Vista on the primary partition several times and activated the key without a problem. This is the first time I am installing it on a different partition.