None of these suggestions worked - very disappointing, I hoped one would!
So I cheated and used Acronis to restore to 14/10/08. All my data is on another drive, so I will merely update my email stuff from C: and press on regardless now that those BBC video clips are opening in AOL (IE) and IE itself.
I occasionally have the same issue and it happens when I run one of the free pc/registry cleaners (although I haven’t found out which one it is yet. In order to fix the problem I have to run the uninstall flash player file from Adobe