INTERNET EXPLORER 9 WON'T REINSTALL

I installed Internet Explorer 9 recently and because various internet
radio stations wouldn't work,
I used system restore to bring back Internet Explorer 8, which worked
well with radio stations.

I used tools to see if their were any repairs needed to files and then
tried to reinstall Internet Explorer 9 and got some message, something
to the effect that it couldn't configure files and left internet
explorer 8 as before.

How can I reinstall The new explorer?.

Thanks.

Roger