450 Write error: No space left on device

I am getting this error message when I try to upload files. My webspace is not full, which I first thought might be the problem.

Can you tell me why or what is causing this?

It looks to be a issue from the hd of the server.

my hd? but I was able to use the website's tool and upload the file, which I really prefer not to use. If it was a problem with my hd, wouldn't I also not be able to upload there either?

Hi, no i mean the hd of the server, your hd is client. But if you say that you can upload with the website tool it can be because ftp quota.