- Make sure that the post is published and not private.
- If it is not a standard post, check if you have searched for the right post type (post_type).
- Make sure that you search for the right type of data – at some places you need to enter a word (name, slug), at other places a number (ID).
- If you are using filter criteria such as a category name or an author ID, try to search without them and check in your admin if these values are correct. Make sure that the post really belongs to this category and author.
- If you need to enter a slug, check if you have any non-standard characters in the word. It should contain only lower-case letters, numbers and dashes.
- Check if there is a conflict with another plugin or a theme: Disable all other plugins and switch to a WordPress default theme. Then try again if the redirection works. If yes, enable the plugins and your theme again, one by one, and after every step try again to find out at which step it breaks.
- If you use many parameters, remove some of them and check if something is found.
- Add the parameter &rutpdebug and see if you have any matching posts.
If you still have no luck, you can ask for help at the forum. Make sure to paste there
- the URL with all parameters that you tried and
- the URL of an example post that you think should be found.