New Player having trouble with download

I purchased Final Fantasy XI: Ultimate Collection
Abyssea Edition [Download] from your Amazon store. I was able to start
my account and redeem my codes for general game play. They work fine on
my xbox 360 version. However, I bought this package specifaclly so I
could play on my PC. The download appears to be corrupted. It loses
connection in about the same place (all 5 times I tried), completes the
download, then extracts and attempts to install. At the end of the
installation process, I am told that the files are corrupted and
installation is not possible.
When I contacted Amazon, they said that it was your file so they couldn't help me and sent me your way. Please help.

I'm sorry to hear you are having an issue installing the game on your system. We have a direct download of the PlayOnline Viewer for the latest version however you will need to see if you can get that installation working for the rest of the game. Everyone is receiving the same distribution of these files, so Amazon is correct in that aspect, we just need to troubleshoot what might be happening with you computer's specific environment. Could you make sure that you are running as the admin on your machine as well as checking the Windows updates for any .net framework and InstallShield updates. We also would want you to check to make sure you've got enough hard drive space for the install and that there aren't any programs preventing you from installing or unpacking a file like AVG, Kaspersky, Norton, etc.

Thank you for your help. I ended up finding a full copy of the download on my boyfriend's computer, copied it and was able to update it for my own use. Once again. Thank you for your kind effort.