I've encountered this several times on a few different sites and I thought I would pose it to the group. It seems like a stupid question, but for the life of me, I can't figure out how it happens or how to fix it (except for one way).
Say, I'm working on a site and I'm coding pages like I normally would (in this case, HTML or PHP is the only language I can remember it happening on) and I code images and files in before they're ready, just kind of as a placeholder for a file that I know will be there later, that I just haven't put in yet. So, the syntax is there for an image, but the image itself doesn't exist yet.
I then upload it to the server via FTP or CMS or what have you.
Then, I visit the site live, obviously not expecting the images to work, but just to test layout/CSS/whatever. Seeing that things are fine, I produce the images and upload them via FTP into the directories referenced by the pages.
I then visit the page and find that my images aren't only not showing up, but giving an error (either 404 or 503 -- I've seen both) in the Chrome property inspector and Firebug. Images that I know are there, know are referenced correctly and have no issues with them. Inputting the URL directly to the image produces the same results.
The only way I can get them to show up (that I've found) is to rename the file something different, change the referencing on the page to refer to the new file and re-upload it.
Has anybody else experienced this? I'm assuming it's a server-side thing, but I have no idea how to fix it or ways to remedy it that don't involve re-uploading and basically redoing everything I've just done.