“File not found.” appears often while navigating wp-admin


I’ve been experiencing this issue with this specific website quite often. I moved it from a staging domain to the production domain and since it’s been doing this. It did not do this on the staging domain (same server).

  1. I did a find and replace on the database to ensure that the staging domain was replaced with the production domain.
  2. I have flushed the permalinks.
  3. I have increased PHP memory for this site

I can’t point to a specific plugin. I’ve used these plugin before on many sites. Everything is up to date. I have not found a pattern to when it appears. If I click between the Posts, Media and Page tabs often enough it eventually happens. I also happens when interacting with the plugins section of the site.

After it has happened a refresh of the page brings it back.

Here are examples: enter image description here

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