As per oscommerce default. You should set following directory permissions via any FTP client e.g Filezilla. Please do the following steps.
- After installation delete install folder.
- Reset the permissions on /includes/configure.php to 644 (if you are still getting the warning message at the top set configure.php to 444 which is read only - this happens on some servers that have been updated for security reasons).
- Set the permissions on /images directory to 777.
- Reset the permissions on /admin/includes/configure.php to 644.
- Create the dir /admin/backups and set the permissions to 777.
- Set the permissions on /admin/images/graphs directory to 777.
- Set the permissions on /admin directory to 755.
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