Font Issues - Displays As Blocks

G'day guys.

I've just reinstalled Win98 on my old computer, and for
whatever reason I have a few programs that aren't
displaying fonts correctly - the characters are appearing
as blocks, such as what happens when you're using a
character using a font that doesn't contain that character
in its set.

The weird blocking is occuring with MSN Messenger,
installation dialogs for Microsoft-developed games (Age of
Empires, Rise of Nations, etc.), and a heap of system-
specific programs. All system fonts are installed.

Any ideas as to what could be causing it?

Thanks.

Decs