abdelrahman abdelrahman
Because the file have immutable flags you need to do this in terminal.
cd ../../www/wwwroot/yourwebsitedirectory
sudo chattr -i .user.ini
sudo chown www .user.ini
After you finish run:
sudo chown root .user.ini
sudo chattr +i .user.ini
This will make the file immutable again and set the root ownership.