slashes problems?

I've just finished to install zen-cart on the localhost to have a look at it. everything went fine & smooth but now... i've got the message saying that configure.php is writable (when i've already changed the permission. so i did notice a strange thing in the path:
E:\webroot\catalog/includes/configure.php
as u can see, there r some slashes in a way and some in the other!

php 5.2.1
Apache/2.2.4 (Win32)
mysql Client API version 5.0.22

i can't find a thread with the same problem: would anyone be so kind to give me an idea to try to solve this problem & get rid of the warning message? i think the lines:
$script_filename = str_replace('\', '/', $script_filename);
$script_filename = str_replace('//', '/', $script_filename);
inside header_php.php should work just fine, so i dunno where he picks up the "" slashes!!!!:huh:

change the permissions to 444 or read only

thanx Merlinpa, i did it already. i'm sure is set to 444 (i've just checked it again) as i'm sure i set it 777 before the installation. it can't be a matter of the wrong path? how can it find the file with the slashes that way? i can't do much in the php.ini file cuz everything is working fine on my local server and i don't wanna change that. plus, after the installation i opened the configure.php and it's properly updated with all the right path. zen-cart is workin' properly, i added personal template and so on... the only thing is that i can't get rid of that warning while the file is already set to 444.
thanx a lot anyway: very kind.