zoran wrote on Aug 23^rd, 2013 at 2:59pm:

Mark, I fixed the problem, something to do with a corrupt service pack 2 so need to download again BUT and there always must be a BUT! lol I registered with an old email address that I cant access and of course my order number has been sent there so I cant even log in to contact support who are on holidays anyway!   ::)

Glad you got it fixed. I don't get that last part about the email address. Is it that you can't get an answer to a Support Ticket or something. When doing a full reinstall, that requires the entry to be removed from the windows registry, reinstalling asks for the email account which was used when the product was purchased (or the email account which has been changed to, by Captain Sim, at ones request), but nothing is sent to the email account itself in regards to installing.
The only things I know that get sent to the email address are the newsletters and Support Ticket responses. :-/

If the problem is in regards to the Manual Offline Activation, you don't need to use a different computer or to get the key_xxxx.txt sent to an email address either. I always do a Manual Offline Activation now and I do it from this computer, which is connected to the internet and does have FSX installed on it.