Whee, someone's using outdated Flash! Sitting duck for hacking. \o/
When you uninstalled it, were you using the universal uninstaller available from
here?
You should try installing the latest version with the manual installer.
32-bit for IE:
http://download.macromedia.com/pub/flashplayer/current/install_flash_player_ax_32bit.exe
32-bit for everything else:
http://download.macromedia.com/pub/flashplayer/current/install_flash_player_32bit.exe
There's also 64-bit versions if you're cool and using a 64-bit browser, but most aren't so I'm not gonna link 'em. Those who use 'em can easily find 'em. :P
EDIT: ... er, I see you're installing the 64-bit version for IE. That would certainly explain the error message if you're using a 32-bit OS and/or browser. o_O
EDIT2: This might be relevant:
You can install Flash Player 11 on 64-bit Internet Explorer on Windows 7.
Note: Flash Player 64-bit is not supported on Windows Vista 64-bit. On Windows Vista 64-bit, install Flash Player 32-bit.