Can’t delete pages or posts

I am having an issue where I cannot delete any posts or pages. When I hit delete the post/page disappears, but when I navigate away, I get a confirmation pop-up that states: “Are you sure you want to navigate away from this page?” Click ok to continue, cancel to stay. I click ok, but when I go back to manage posts/page, the post/page I just tried to delete is still there.

I’ve read elsewhere on the forum that this is due to a bad upgrade. But I’ve had no trouble right after the upgrade so it’s a more recent issue. I’ve tried deactivating all my plugins but no luck.

Any help would be appreciated. And please, if I need to be clearer on anything to help solve this, let me know.

Thanks in advanced.