http 404 error for other php pages

NOW the URLS such as http://localhost/manual/new_features_1_3.html and http://localhost/index.html.en etc. are available on IE 5.0 to me. But the site named "try" still doesn't work.(ie. the URL http://loaclhost/try/index.php still gets HTTP 404 ERROR, the same question occured on some other sites under the localhost. The sites are edited with Frontpage 2000(PWS is nstalled, however it's stoped when I 'm running Apache) The path for the "try" folder is available too. The system is WIN 98 SE(including IE 5.0) of Chinese version, also including Apache1.3.20+PHP4.06 Please give me some advice to resolve it! THANKS Baker