Links to my own posts Not Working

It’s come to my attention by a reader that the links to my own posts on my site are not working. Instead, they are directed to an error message. To clarify or give an example…I write a post about something and realize I have written a previous post I want to reference in regards to the one I’m writing about, so I add a link to it for them. They click on that link and an error occurs instead of it directing them to the post.

I am curious. I added the Plugin W3 Total Cache. Would clearing the cache cause this problem?

Thanks for the help!