OS 10.5 - Uploading file issue

Hi,

Of recent I have been using a few of those free online file hosting sites to upload a few of my files for friends. Mainly my garageband creations + a few other things. And I upload the file and it works as it should and I wait for the file to transfer from my imac to their server. And as the file is done it my net browser tries to load the page saying upload successful and here is the download link. But it always fails with a message similar to this:

Zero sized reply: this document contains no data.

And I check the site to see if the file is uploaded and nothing. I've tried safari and firefox with many different file hosting sites all with the same issue.

Does anyone know what the issue is here? Cause it is baffling me something silly.

Thank you.