If wp_backup fails, the most common causes are disk space and file permissions.
Disk full
The plugin writes the snapshot to wp-content/uploads/wpfc-backups/ on your WordPress server. A full snapshot of a small site is usually 50–200 MB; a WooCommerce store with media can be several GB. If the host’s disk is full, the backup will fail before any file is written.
To check: log in to your hosting control panel (cPanel, Plesk, Hostinger hPanel, etc.) and look at disk usage. If you’re at or near the quota:
- Empty the trash in WordPress (Posts, Pages, Media — each has its own trash).
- Delete old snapshots from
wp-content/uploads/wpfc-backups/. The plugin keeps the latest 5 by default; older ones are pruned automatically only when a new backup succeeds, so a long string of failures can leave debris. - Clear large caches (W3 Total Cache, WP Rocket, LiteSpeed Cache, etc.).
- If you’re still tight, ask your host to raise the disk quota.
Permission error
If the disk has space but the backup still fails, the WordPress user may not have write permission on wp-content/uploads/. The directory needs to be writable by the web-server user (typically www-data, apache, or your cPanel user). A working permission set is 755 on directories and 644 on files; some shared hosts need 775/664.
To verify: SSH or use your host’s File Manager, navigate to wp-content/, and check that uploads/ exists and is writable. If wpfc-backups/ doesn’t exist, the plugin will try to create it on first run; that creation also requires write permission on uploads/.
Still failing?
Open a ticket at /create-new-ticket/ and include the exact error message returned by wp_backup, your hosting provider’s name, and the output of df -h (or your host’s disk usage screen).