this problem happens quite a few times on my several installations. after a while, login as admin won;t be able to view forum module properly. all i can see from it is the title. all the forums are gone. if i login as host or other registered users it's back to normal. i create a new account and assign administrator role to it. and i use it to access the forum module without problem. does this happens to you? thanks!

thanks for the reply, leupold. actually it only happens to the forum module while login with the default admin account. if you login as other accounts, the forum module works just fine.