"ret_code":50 The specified path is invalid. (code: 161) in core\cache\file.php

[lordisp]

I'm installing AbanteCart on Azure WebApps using MariaDB with InnoDB, so I figured already lots of issues out but have still some troubles such as path issues. During the installation process I get the following error from the wizard:

"ret_code":50 The specified path is invalid. (code: 161) in core\cache\file.php on line 398

395        $new_path = $path.'_trash';
395        $renamed = false;
397        if (!is_dir($new_path)) {
398            if (rename($path, $new_path)) {
399                $path = $new_path;
400                $renamed = true;
401            }
402        }

All prerequisites should be fine; also the DB Connection works after changing MyISAM to InnoDB