I having problem accessing the webpage (localhost)

I installed apache 2.0.50 and was working fine, I could see the welcome page from apache, suddenly I have the error

"Forbidden
You don't have permission to access / on this server.

Additionally, a 403 Forbidden error was encountered while trying to use an ErrorDocument to handle the request.


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Apache-AdvancedExtranetServer/2.0.50 (Mandrakelinux/5mdk) mod_ssl/2.0.50 OpenSSL/0.9.7d PHP/4.3.8 Server at 127.0.0.1 Port 80"


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can somebody please help me or drive me to solve this problem

It's hard to tell based on what you just described. More info would be useful.
What sort of page is that? Does it contain dynamic content? Show relevant error log content.