Windows Messenger fails to load

[Boon]

I know most of you think that Windows Messenger loading
with Outlook Express is a curse, but I think its rather
neat. However, when I installed AOL's Messenger, I
accidentally set it to be the default messenger. This
caused AOL messenger to load up instead of Window's
Messenger when I open OE.

However, i set default back to Windows Messenger (through
addremove progs, set defaults).

But when i get to Outlook Express, when i go to Tools >
Windows Messenger > send instant message i get the
following error: "Internet Explorer Install on Demand
failed to install Windows Messenger"

How do i fix this problem?

Boon