Internet access: Juno dial-up. Browser: Firefox 18.0.2. OS: Windows XP Pro. No antivirus programs. I have been unable to download software from three Web sites. When the Firefox Downloads window opens, it lists the file which I want to download, but under that file name is a message which reads, "Canceled - (Web site name)." What causes a download to be canceled? How can I prevent this and obtain the download? The software which I have been unable to download is: from adobe.com: Acrobat Reader and Flash Player; from kodak.com: the software to support my Kodak digital camera; from mozilla.org: Thunderbird. If I follow Adobe's instructions and double-click on the file name in the Downloads window, the download proceeds, but it appears to be a sham download. When it is finished, nothing more happens, and when I search the entire hard drive for the supposedly downloaded file, it is nowhere to be found. The data seem to have simply vanished. I have taken two screen shots of a canceled Thunderbird download, but I don't see how to attach them to this question.