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Upgrading from 2.2.17 to 2.2.19 is not a succes. I use the expanded install, because the PHAR version gives a blank page. When I install I first get the message that config.php are 777. This is not true, but if I give the rights again it works. At the end of the install proces I get Permissions problem: cannot overwrite /index.php. Never had this before. What's wrong?

It's solved. Used index.php from other version