My Error Log

Hi Martcol,

This is caused by interference from another plugin/theme. Another plugin/theme is sending sending output too soon. This is often caused by a poorly written plugin or theme doing something like ending a PHP file with closing PHP tags.
You can possibly narrow down which one by following these instructions https://semperplugins.com/documentation/how-to-troubleshoot-issues-with-all-in-one-seo-pack/ with debug display on.