By default the forums are disabled
you need to goto
http://yoursite.com/tikiwiki/tiki-admin.php?page=forums
you will find this link in the admin config
and then create a forum
/tikiwiki/tiki-admin.php
http://yoursite.com/tikiwiki/tiki-admin_forums.php
when trying to create the forum i got the message
This feature is disabled: feature_forums
http://doc.tikiwiki.org/Forum+Admin?bl=y
ok looks like you need to goto
/tikiwiki/tiki-admin.php?page=features to enable the features
The following list of changes has been applied:
preference feature blogs enabled
(preference name: feature_blogs)
preference feature calendar enabled
(preference name: feature_calendar)
preference feature forums enabled
(preference name: feature_forums)
preference feature galleries enabled
(preference name: feature_galleries)
preference feature polls enabled
(preference name: feature_polls)
preference feature wiki disabled
(preference name: feature_wiki)