Page not found

hi, i want to ask this, before i used to have urls like this :
t2/etc.
now i got the urls based on the topic of the thread.

so url has been changed
google still contains pages from old url when users visits it says 404 not found.
how to fix this . like redirect that page to my main site ?

please help. i believe it can be done with .htaccess or something ?

Hello D4, the right place to get advice for redirects is in the URL Rewrite Settings forums.