php rename (.): Access is denied. (code: 5) set access permissions on folder

[samuel491]

SO Windows Server 2008, IIS/7.5 Webserver, PHP Version 3.5.25,
Admin Panel: Parallels Plesk Panel 11.0

.php files with php rename() function generates the following error
PHP Warning: rename (.): Access is denied. (code: 5)

May be due to lack of permissions for the folders that contain the files to rename?

Im tring to grant permissions but I cant modify anything ...

I login to Parallel with a Owner user with all privileges
Click File Manager
On the directory to set access permissions, click padlock icon
any attempt to change the permissions is denied


there are the following groups:

Administrators
SYSTEM
Plesk Domain User (domainname)
Plesk IIS Anonymous Account (IUSR_domainname)
Plesk IIS Worker Process Identity Account (IWPD_6 (domainname))
Hostname support (support)

for each group you can Allow/Deny privileges:
[]Full Control
[]Modify
[]Read & Execute
[]List Folder Contents
[]Read
[]Write

Groups: Administrators, SYSTEM got all privileges

IUSR_domainname has only one privilege: [v]List Folder Contents

IUSR_domainname should be my target, the public user who launches a request from the browser, is it rigth?

any attempt to change the permissions are denied
inheritance permissions options are denied too

Thank you for help