How to enable Flash in IE10 Metro on Windows 8 and Windows RT
Internet Explorer 10 Metro mode has limited Flash support and unfortunately we need to resort to hacking a file in order to get it to work, for now. A new method has come up and it allows us to have Flash support at last. "As we all know Windows RT/8′s IE Metro browser has limited flash support based on a whitelist. However a lot of sites are not (yet) whitelisted and hence do not work as desired. So I did some digging in the whitelist mechanism and found a way to hack it," the post explains.
To apply the hack, simply go to C:\Users\[USER_NAME]\AppData\Local\Microsoft\Internet Explorer\IECompatData\iecompatdata.xml and open the file. Just add your favorite site to the whitelist and you can get full flash support.
This method works on both Windows 8 and Windows RT.