Messenger won't update

[gtghm]

I have messenger 4.7 and I want to update to the new
messenger 6. My 4.7 doesn't go look for the new 6 and
update and if I download and install 6 buy itself I get 2
copies of messenger.
How do I either uninstall messenger 4.7 so that I can have
have only one version of messenger or how do I get 4.7 to
go out and get the update?

Thanks,
"g"