I think I understand. I belong to a few Yahoo groups and I am a moderator of
a few. My message rules for Yahoo groups are written to use the "To" address
for moving messages to the folder I have for each group. I actually use "To
or CC". That has worked for me for years. There are a few that don't get
caught that way; some messages are sent using bulk emailing and even though
Yahoo seems to not be confused, Windows Mail is confused by that.
If I must, I sometimes use the group name such as "[GMF]" (with brackets)
but I resort to that only if necessary.
So it should work to use the "To" address. You say it is not working but I
suggest you look closer. Are you totally sure that the address you have in
the rule is the address that is in the message? Probably when you look, you
will see a discrepancy.