I can no longer install or use programs or files I download over the Firefox browser because they do not appear on the downloads list. No matter what kind of file I try to download, when it is finished downloading, I get the popup message that downloads are completed,but when I go to tools/downloads, there is absolutely nothing listed there. I did not make any changes to the settings, but after the Firefox updates about two months ago, this problem began to occur sporadically''' ''', but now occurs every time I download anything via Firefox for installing, etc.