Upgrade completed(vb4.2>5.23) ,but The requested URL /vb5/forum/-aa/-am was not found on this ser
 

Upgrade completed ,but The requested URL /vb5/forum/-aa/-am was not found on this server.

As title

Upgraded from VB4.2 >>VB5.23 completed
System:Fedora 17
Mysqli :5.5.28
Apache 2.2.22
PHP 5.4.9

I can see the homepage normally,
(PS:I can see homepage noamally at firefox browser,but see nothing at IE 10 (Win 8))
but when I tried to enter forum page ,the error message just as title,and when I tried to login ,the error message as below
>>>
Not Found
The requested URL /vb5/auth/login-form was not found on this server.

Plese help!!