Cannot Modify Header - Error

Receiving the following message in our error log. 2.4.8.5 running php 5.6

I have not been able to determine what action is causing the error. Also noticed that the HTML editor is not working when modifying html for things like static text blocks.

Any help is appreciated. Thank you.

[14-Nov-2019 08:43:39 America/New_York] ojs2 has produced an error
Message: WARNING: Cannot modify header information - headers already sent by (output started at /home/radjr1/domains/wmpllc.org/public_html/ojs/lib/pkp/lib/smarty/Smarty.class.php:1302)
In file: /home/radjr1/domains/wmpllc.org/public_html/ojs/lib/pkp/classes/core/PKPRequest.inc.php
At line: 87
Stacktrace:
Server info:
OS: Linux
PHP Version: 5.6.40
Apache Version: N/A
DB Driver: mysqli
DB server version: 5.5.63-MariaDB

Hey @radjr

These sorts of bugs can be hard to fix, but have you made any changes to class files, like possibly adding a blank line before an opening <?php tag or after a closing one? Somewhere, content is being sent to the browser before OJS sends headers.

Cheers,
Jason

Thanks Jnugent. No, this is a 2.4.8.5 install from scratch and then our 2.4.8.4 data was laid on top of it. I did not touch class files…don;t know what they are actually. Thanks for your help.