Wordfence needs to create and update files in wp-content/wflogs. The plugin writes logs, firewall rules, and attack data to this folder. If the web server process lacks ownership or proper permission bits, the write operation fails. The error appears in the dashboard and prevents the firewall from optimizing.
The failure also occurs when PHP restrictions, SELinux policies, or a read‑only filesystem block access. Disk quota exhaustion produces the same symptom. The plugin reports the problem as an inability to write to the wflogs directory.