ftp download file problem

[qadeer_ahmad]

i am trying to download a file from my server but it giving error

Connected as [e-mail]
Warning: ftp_get(): Prohibited file name: \download\aaa.zip in /home/abc/public_html/ftp1.php on line 25
There was a problem

while i am using this script

<?
$conn_id = ftp_connect($ftp_server) or die("Couldn't connect to $ftp_server");

// try to login
if (@ftp_login($conn_id, $ftp_user, $ftp_pass)) {
echo "Connected as $ftp_user@$ftp_server\n";
} else {
echo "Couldn't connect as $ftp_user\n";
}
//-------------------------------------------------------------------------------//
// define some variables
$local_file = 'c:\aaa.zip';
$server_file = '\download\aaa.zip';

// try to download $server_file and save to $local_file
if (ftp_get($conn_id, $local_file, $server_file, FTP_BINARY)) {
echo "Successfully written to $local_file\n";
} else {
echo "There was a problem\n";
}

// close the connection
ftp_close($conn_id);
?>

can some body guid me

[qadeer_ahmad]

i also try using file in the root like this

$local_file = 'c:\aaa.zip';
$server_file = 'move.js';

now error is

Connected as [e-mail]
Warning: ftp_get(): Can't open move.js: No such file or directory in /home/comsdev/public_html/ftp1.php on line 25
There was a problem

but file is present on root and this file is also in root
i could not understand error is?

[qadeer_ahmad]

i chnage address and it working , address is

$local_file = 'c:\aaa.zip';
$server_file = 'www/download/aaa.zip';

and now as i write messege appear

Connected as [e-mail] Successfully written to c:\aaa.zip

but no file present at c:\aaa.zip

where is my file gone...