Since a few of the search results that lead people to view this site appear to be related to my posts about BBC iPlayer troubles, here is another problem that I have encountered.
Before going on holiday outside of the UK, I tried downloading a few programmes on the iPlayer on my Mac laptop. After a few seconds each download attempt would fail.
Fortunately this was a known issue, and the BBC site has a workaround:
Basically it involves uninstalling the currently installed version of Adobe AIR and installing an older version.