Hello @torsten3d,
The trace log indicates that the error occurred during a login attempt, and it seems to happen sporadically. At present, the wp-admin page of the specified website is functioning correctly, and I was unable to replicate the issue using the latest version of WordPress.
It’s possible that a component of your website is conflicting with the Security Optimizer. My advice is to temporarily deactivate your other website plugins one by one, testing the login process after each deactivation while keeping the Security Optimizer plugin active. Should the error continue even with all other plugins disabled, try switching to the default WordPress theme for further testing. This approach will assist you in pinpointing the component that is causing the conflict. Once you identify the problematic plugin, I recommend reviewing its settings to ensure there are no overlapping features or configurations that might be causing interference with Security Optimizer.
If you need any further assistance from our side, feel free to re-open this thread.
Best Regards,
Tsvetan Mitev