federicoF-28

Problem:
The client is experiencing a '400 bad request, request header or cookie too large, nginx' error after opening 4-6 pages in the WordPress admin. This issue started after installing WPML and persists until cookies are cleared, but reappears upon further navigation.
Solution:
We recommend checking if this issue occurs across different browsers such as Chrome, Firefox, and Safari. Although we couldn't find a similar case in our records, we suggest following the steps in these articles to troubleshoot and potentially resolve the issue:

• PC Risk: How to Fix 'Request Header or Cookie Too Large'
• NameHero: How to Fix '400 Bad Request, Request Header or Cookie Too Large'

If these steps do not resolve the issue, it might be due to an outdated solution or a different underlying problem. We highly recommend checking related known issues, verifying the version of the permanent fix, and confirming that you have installed the latest versions of themes and plugins. If the problem persists, please open a new support ticket.