I used restore to get Giant AntiSpyware back because Windows Defender was not
an improvement. I have already tried the link you suggested to Mark and you
they ask you to provide a code that is sent when you purchased the product, I
don't think this will apply to the download of the free Beta 1 software from
Microsoft.
Microsoft Antispyware is not the same product as Giant Antispyware. There
are still users with valid subscriptions to Giant Antispyware, apparently,
and Mark may be one of those.