Have you tried downloading any other AIR applications? From http://www.adobe.com/products/flashplatformruntimes/gallery/ for example

For me no AIR application can be downloaded (I consistently get the Error # 2032 message) which points to a consistent issue. My BBC iplayer AIR application stopped working some time ago and I have been unable to resolve this until this am.

The workaround is to get to the application download page and look at the page in source code in order to see the URL for the AIR application installer. Then use this URL in the browser window. For me the installer can then be downloaded to the hard disk and fired up from there. Unfortunately, I dont have any knowledge of why this works nor can I read the source code so I dont understand why the .air installer for iplayer does not appear in the BBC iplayer installation page code - some intermediate software?

However, by using a laptop (my problem is on my desktop) running VISTA Home (XP SP3 on the desktop), both using Firefox 3.6.13 but ESET NOD32 Antivirus and Windows Firewall on the laptop (Norton Internet Security 15.0.0.60 on desktop) I have been able to download the BBC iplayer installer using the laptop direct into the shared docs folder of the desktop as both are on a home network using the same router.

None of the recommended other "solutions" that I have seen published had any effect eg turning off firewalls, reinstalling AIR, reinstalling Flash Player, using tools to remove AIR, updating Windows Software Removal tool to remove iplayer, clean installation of iplayer, ensuring only downloaded via Administrator User Account, emptying browser caches etc etc

Can someone from Adobe please look into this and advise as I have seen a lot of postings about this on the net and technically ignorant users like me stand no chance of sorting this themselves particularly when the suppliers of the AIR installations say "there is nothing the matter with our software."