It could certainly mean your FTP server is down.
Go to your FTP account and try to log in and see if you can log in.
Are your images showing up on your auction listings that are running on eBay?
If they are, are you sure you have space left on your FTP account. Meaning what is the limit on your FTP space. Some FTP accounts will literally shut you off if you exceed your limit. Others will simply bill you for the overage. You should check to see what your FTP account allows.
The other thing you can do is paste one of the image url's into a new browser window and see if it displays. If it displays then your FTP server is running and something else is wrong.
let me know
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