I get a "URL not found" error, but the image is on the server I have a Drupal site which I have just migrated to a different Linux server for development. The site seems to be working more or less.

However, one problem persists: None of the images is shown. Instead, if I click on an image, it says: "Requested URL not found."

What is more, all of these images exist in the proper directories. I checked .htaccess for RewriteRules but did not find anything relevant. I have also played with permissions. Currently the entire root of the site is set to 755.

What can I do to make the images work?
If you have some sort of caching service like "Varnish" active you may want to try clearing it's cache. 

This sometimes happens to me and I just need to clear my browser's cache.