php mysql htaccess used for the first time - php

Question

i am using the php and mysql to create a profile page using the get methode to get the username from the url like this (http://localhost/Unnamed%20Site%202/resources/username) so i used the .htaccess but the problem was that the root folder where i put the .htaccess was disappear and i get an error msg from the browser :
Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.
Please contact the server administrator, admin#localhost and inform them of the time the error occurred, and anything you might have done that may have caused the error.
More information about this error may be available in the server error log.
anyone can help me??
this is the appache_error.log
[Mon Mar 18 19:13:05 2013] [error] [client 127.0.0.1] PHP 1. {main}() C:\\wamp\\www\\Unnamed Site 2\\resources\\profile.php:0, referer: http://localhost/Unnamed%20Site%202/resources/
[Mon Mar 18 19:13:16 2013] [error] [client 127.0.0.1] File does not exist: C:/wamp/www/favicon.ico
[Mon Mar 18 19:13:21 2013] [error] [client 127.0.0.1] File does not exist: C:/wamp/www/favicon.ico
[Mon Mar 18 19:13:52 2013] [alert] [client 127.0.0.1] C:/wamp/www/Unnamed Site 2/resources/.htaccess: Invalid command 'RewriteEngine', perhaps misspelled or defined by a module not included in the server configuration, referer: http://localhost/Unnamed%20Site%202/resources/account-setting.php
[Mon Mar 18 19:13:52 2013] [error] [client 127.0.0.1] File does not exist: C:/wamp/www/favicon.ico
[Mon Mar 18 19:23:09 2013] [alert] [client 127.0.0.1] C:/wamp/www/Unnamed Site 2/resources/.htaccess: Invalid command 'RewriteEngine', perhaps misspelled or defined by a module not included in the server configuration, referer: http://localhost/Unnamed%20Site%202/resources/profile.php
[Mon Mar 18 19:23:09 2013] [error] [client 127.0.0.1] File does not exist: C:/wamp/www/favicon.ico
[Mon Mar 18 19:23:09 2013] [error] [client 127.0.0.1] File does not exist: C:/wamp/www/favicon.ico
[Mon Mar 18 19:23:11 2013] [alert] [client 127.0.0.1] C:/wamp/www/Unnamed Site 2/resources/.htaccess: Invalid command 'RewriteEngine', perhaps misspelled or defined by a module not included in the server configuration, referer: http://localhost/Unnamed%20Site%202/
[Mon Mar 18 19:23:11 2013] [error] [client 127.0.0.1] File does not exist: C:/wamp/www/favicon.ico
[Mon Mar 18 19:23:12 2013] [error] [client 127.0.0.1] File does not exist: C:/wamp/www/favicon.ico
[Mon Mar 18 19:23:13 2013] [error] [client 127.0.0.1] File does not exist: C:/wamp/www/favicon.ico
[Mon Mar 18 19:23:14 2013] [error] [client 127.0.0.1] File does not exist: C:/wamp/www/favicon.ico
[Mon Mar 18 19:23:16 2013] [alert] [client 127.0.0.1] C:/wamp/www/Unnamed Site 2/resources/.htaccess: Invalid command 'RewriteEngine', perhaps misspelled or defined by a module not included in the server configuration, referer: http://localhost/
[Mon Mar 18 19:23:16 2013] [error] [client 127.0.0.1] client denied by server configuration: C:/Apache2, referer: http://localhost/Unnamed%20Site%202/
[Mon Mar 18 19:23:16 2013] [error] [client 127.0.0.1] client denied by server configuration: C:/Apache2, referer: http://localhost/Unnamed%20Site%202/
[Mon Mar 18 19:23:16 2013] [error] [client 127.0.0.1] client denied by server configuration: C:/Apache2, referer: http://localhost/Unnamed%20Site%202/
[Mon Mar 18 19:23:16 2013] [error] [client 127.0.0.1] client denied by server configuration: C:/Apache2, referer: http://localhost/Unnamed%20Site%202/
[Mon Mar 18 19:23:16 2013] [error] [client 127.0.0.1] client denied by server configuration: C:/Apache2, referer: http://localhost/Unnamed%20Site%202/
[Mon Mar 18 19:23:16 2013] [error] [client 127.0.0.1] File does not exist: C:/wamp/www/favicon.ico
and this is the profile.php
// updatede for using the GET methode for ge the data nedded from the url
if(isset($_GET['u']))
{
$username = mysql_real_escape_string($_GET['u']);
if(ctype_alnum($username))
{
//check user exist
$check = mysql_query("SELECT user_name, first_name FROM user WHERE user_name = '$username' ")or die(mysql_error());
if (mysql_num_rows($check)==1)
{
$get = mysql_fetch_assoc($check);
$username = $get['user_name'];
$fname = $get['first_name'];
}
else
{
// this line is to redirect the unexist users to the index.php
echo "<meta http-equiv=\"refresh\" content=\"0; url=http://localhost/Unnamed Site 2/resources/index.php\">";
exit();
}
}
}
?>
.htaccess
RewriteEngine On
RewriteRule ^([a-zA-Z0-9_-]+)$ profile.php?u=$1 [L]

Answer 1

This error message
[Mon Mar 18 19:13:52 2013] [alert] [client 127.0.0.1] C:/wamp/www/Unnamed Site 2/resources/.htaccess: Invalid command 'RewriteEngine', perhaps misspelled or defined by a module not included in the server configuration, referer: http://localhost/Unnamed%20Site%202/resources/account-setting.php
hints at a missing mod_rewrite module. You must first install and/or configure it, before you can use it.