I was getting same forbidden error (In windows machine for wamp), after lot of r & d I found that there is need to change default virtual host in httpd-vhosts.conf file which is present in:
C:\wamp\bin\apache\Apache2.2.17\conf\extra
(change directory c:/wamp/www to what you want)
From :
ServerAdmin webmaster@localhost
DocumentRoot “c:/wamp/www”
ServerName localhost
ErrorLog “logs/localhost-error.log”
CustomLog “logs/localhost-access.log” common
To:
ServerAdmin webmaster@localhost
DocumentRoot “E:/wamp/www”
ServerName localhost
ErrorLog “logs/localhost-error.log”
CustomLog “logs/localhost-access.log” common

اگه بخشی رو متوجه نشدید بگید توضیح بدم

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