PMDG 747 400 QOTS FS9

I suspect that my beloved 747 400 Queen of the Skies is no longer supported but I'm going to ask anyway. Facts is I purchased the subject aircraft software, retail, on disc v 1.0 (I think). Somewhere along the line I downloaded and installed the v1.2 update and everything went swimmingly until a hdd was infected with a virus. Not the hdd I access fs9 from but the hdd with all the installation files. The upshot is that many of my programs no longer worked. FS9 being one of them. I got rid of the virus and re-installed all of the damaged programs but now I cannot re-install my 747 400 as it returns a message to the effect that I already have v1.20.000 installed and quits the installation. There must be a registry hook somewhere that I need to modify but I've looked and can't find any. Can you point me in the right direction please. The os is win7 64 bit.

I point out that this is not a terminal problem as I purchased the same aircraft for my fsx installation, as well, so it's not as though I cant fly her but I'd really like to get her back into fs9 as I fly around Australia with VOZ 1.8. Very cool scenery. Very cool aircraft. Thank you. FWIW, the quality of that purchase spurred me to purchasing the 737 800/900 (fs9), JS4100 (FSX), 747 400/F/8i (FSX), 737 800/900 NGX and still my PMDG Fleet will grow as I finally purchase the MD11 in a weeks time. The upcoming 777 for me is a 'lay down misere'.

Jon Shearer