WordPress instance inside a sub-directory on Plesk server shows "404 Page not found" errors for existing categories or posts

Alexander Davydov

Updated January 13, 2026 19:07

kb: bug kb: fixed Plesk for Linux ext: wptk

Applicable to:

Plesk for Linux

Symptoms

Existing Posts or Categories from a WordPress instance installed under sub-directories (e.g. /httpdocs/test) return "404 Page Not Found", "Not Found" or "Nothing Here" error.
Permalinks at WordPress admin Dashboard > Settings > Permalinks page are set differently than "Plain" (e.g. Post Name) at the WordPress instance installed under the sub-directory.

Cause

Product issue:

#EXTWPTOOLK-8578 "Block author scans and Enable bot protection security measures no longer break WordPress sites installed in a subdirectory."
Fixed in:
- WP Toolkit 5.9.2 10 February 2022

Resolution

Please consider updating your server:

How to update Plesk extensions

Workaround

Apply one of the following workarounds:

Use "Plain" permalinks:

Login to the WordPress admin Dashboard of the sub-directory instance.
Go to Serttings > Permalinks page.
Select Plain option and click Save Changes.

Revert Security Measures "Block author scans" and "Enable bot protection":

Revert the Security Measures "Block author scans" and "Enable bot protection" on the main WordPress instance (/httpdocs) and under Wordpress instances installed to subdirectories (e.g. /httpdocs/test), as described below:

Log into Plesk.
Go to Domains > example.com > WordPress > select the WordPress instance in question > Security Status or Security page and press Check Security button.
Select Block author scans and Enable bot protection, if both are found applied, otherwise select the one found and press Revert button:

Security_Measures.png
(100 KB)