If you ran $prefix/bin/check_perms OK then look at youf httpd.conf file.
It may be that a -FollowSymLinks Option is being applied that is stopping
the symbolic link in $prefix/archives/public directory to the public list's
archive being followed. This is mentioned in the MM INSTALL document.
On the home page to Mailman, there is a link:
"To see the collection of prior postings to the list, visit the
Schoolhouse-news Archives."
When I click on the link I get:
Forbidden
You don't have permission to access /pipermail/schoolhouse-news/ on this
server.