I have rebuilt an old ASPX CMS website to plain PHP website and also we changed hosting company and now using Apache.
Google still show old urls that doesn't exist anymore.
To fix that I added a 404 redirection in htaccess.
ErrorDocument 404 /index.php
It's working well if the old url is www.mysite.com/old.aspx
but it's not working correctly if the old url is www.mysite.com/en/
What it does, it's display only the new content of the index but not pulled the css and js (header and footer are included file) and the url stay the same no redirection to the new index.php.
Thanks for your help