When I go to marketing -> Newsletter Subscribers I can see the first 20. But if I try to go to the next page in the list, or extend the display results to a number greater than 20, I get a 404 error. I also get an error when I try to export to a csv. All other import and export functions in the admin work without issue, same with viewing any other lists.
Hi @etchalifou5534
Please check with controller
vendor/magento/module-newsletter/Controller/Adminhtml/Subscriber/Index.php
You need to check conditions of ajax, is it working fine or not.
if ($this->getRequest()->getParam('ajax')) { $this->_forward('grid'); return; }
Also check with Block file functions.
vendor/magento/module-newsletter/Block/Adminhtml/Subscriber.php
It may help you to resolve issue.