Well first of all you should switch to a better faster and safer alternitive to Internte Explorer such as
Mozilla Firefox or
Opera 8.
Maybe you should make sure that you are not running out of space/bandwidth on the server. Maybe your host does not alow .mp3 extensions their server. Also try restarting your FTP client or try a diffrent one. Renew your IP address. Also did you try restrarting your computer?
also this might be your internet connection's falut
If all of that fails then I don't know what to do, try contacting your server.
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