After i introduced sling error handling i.e /apps/sling/servlet/errorhandler/404.jsp in my project i 'm facing the below issue on author
When i open a page on author instance being a anonymous user , It takes me to no resource found page instead of log in page. below is the screenshot
If i log in via crxde and open the page it opens fine, Please let me know if someone has faced similar issue and know the solution.
I m using AEM 6.3 version and i have 404.jsp as well as 404 page in place. It works fine on local but it behaves as mentioned above on higher environments.
You mentioned that it works if you login before (e.g. with CRXDE). So I assume that you don't handle properly in your 404 code the use case if someone is not logged in. You need to check the permissions and depending on the result you'll need to redirect to the login page.
I would recommend to check the AEM default 404 handler code, there you will see all the different cases it handles.