My IE8 has suddenly started defaulting to the 64-bit version. I have no idea how or why this has happened, but I suspect it might be linked to the Browser Choice Screen that Microsoft was recently forced to display by EU law.
However, many web sites will not display correctly in IE8 x64 (eg. sites that use Adobe Flash or Microsoft Silverlight). I have the 32-bit version of IE pinned to my taskbar and if I launch it manually, everything is fine. But when I click on a URL from another program and IE is not already running, then the 64-bit version gets launched. This really messes with programs like BBC iPlayer which rely heavily on Adbobe Air and Flash.
So, how do I get IE8 32-bit version to be the default version again? I've tried using the "default programs" control panel and that doesn;t make any difference (in fact, it doesn't give the choice between x84 and x64 versions, it just lists "internet explorer").