Less css is not writable

1) Make sure you have an up-to-date theme version.
2) Please try to apply 755 or 777 CHMOD to:
…/wp-content/themes/THEME_NAME/css/custom.less

…/wp-content/uploads/

…/wp-content/uploads/wp-less/THEME_NAME/css/ folder and files inside.

Then you need to navigate to Theme Options -> General and click “Save Options” button. Warning message will not bother you after that.

3) Please check upload path is default (in Settings > Media or in WP-config.php)

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