[Koha] OPAC and Intranet not accessible via Internet

Hi, I have difficulties to make library Opac accessible via Internet. Opac is working properly on the local host. I changed "localhost" with IP number but without success (http://localhost/cgi-bin/koha/opac-main.pl <http://xxxxxxx/cgi-bin/koha/opac-main.pl> ). The same problem is with the "Intranet." Can anybody advise me how to fix the problem? MySQl and Apache are installed according to the instructions (as far as I can see). I use Win XP pro, Koha v.2.2.9; Apache v.2.2.9, My SQL v.4.1, ActivePerl 5.8.9, YAZ toolkit. I'm connected via LAN. Sincerely,