Well the only solution I could find was in Spanish but as far as I could understand it, it says to uninstall live messenger, if possible go back to a restore point before you installed it, reboot your computer and reinstall it. Making sure you select Messenger 2011 some place during the installation.
It seems a lot of people are having this problem but I find few suggestions for fixing it.
I don't have any other ideas, if you have a restore point before the change I'd try that if it were me.
It shouldn't effect anything that was installed before the restore point but you would probably have to reinstall anything that was installed or updated afterwards.
I've installed Windows Live components on my computer with no problems but I don't have any idea what the conflict is in yours.
Did you install just Windows Live Messenger, or the whole Windows Live package.
If you did the whole package then maybe just installing the components that you are going to use would help.