Hi mulko,

Does this happen with any files that you download regardless of the source or just with the ones that you download from the unstable server? Also, if you try the same download with another browser does it do the same?

As far as I know, it only happens with files I download from the specific server. But I haven't downloaded a lot from other servers, so I don't think I've experienced download trouble elsewhere. I don't use other browsers, but I'll try Chrome for a while and see how it goes.

Here's an example: I downloaded a file april 4th. The download failed the first time, succeeded the second time. (I don't use the "retry" button in the download list, I click the download button on the website once more). The file appears twice in the download list, first one as "failed" and then one successful (timestamp 1:56 PM april 4th).

I work on the file for a few days, and deliver it to my client (last version saved 1:36 PM april 7th). After that, I don't touch the file.

I start Firefox several times in the following days without anything out of the ordinary happening.

Then the file is suddenly deleted when I start Firefox on april 10th at 9:16, and reappears at the top of the download list in Firefox as "failed" (timestamp 9:16 PM april 10th). The two "original" downloads have now disappeared from the download list.

It seems like Firefox makes a new attempt at the original failed download, fails again, concludes that the file can not exist locally and therefore deletes it. I save the files in a Dropbox folder. Could that have anything to do with it?

It happens only when I start Firefox. I've made it a habit when I start Firefox always to check the download list. If one or more files suddenly reappear as "failed" at the top of the list for no apparent reason, it means that they have been deleted.

Upgrade to version 29.0.1 seems to have solved this problem.

Sorry, I was wrong. The upgrade just reset the download list. Problem persists.

I don't have the same problem in Chrome, but Chrome gives a bit more info. When the downloads fail in Chrome, the reason seems to be a problem with the write permission in the Dropbox folder. Chrome doesn't go back and delete the file later, though.

I'll take screenshots next time it happens, to show you exactly what is going on.

Firefox doesn't remove files that you have downloaded.
A possible cause is that your security software is locking the file for inspection and that makes Firefox fail to complete the download and move the file from the system %TEMP% folder to the final location.
Your AV software may also be removing these files.

Try to disable the real-time (live) scanning of files in your anti-virus software temporarily to see if that makes downloading work.

See:

• http://kb.mozillazine.org/Unable_to_save_or_download_files
• browser.download.manager.scanWhenDone = false

Try configuring FF not remembering history. Then watch what happens.

cor-el: It is definitely Firefox that causes the files to be deleted. Absolutely no doubt. Please read the description properly. It only happens when I start Firefox.

stanlyct: Yes, it looks like that did solve it. Although it is more a workaround than a proper solution. Thanks a lot. The question is if I can live without my browsing history (it is deleted together with the download history - very annoying).

Hi Mulko, It seems some downloaded malware is hidden in your history or cache causing to either interrupt your actions on FF or deleting it. If suspicious activity found by your antivirus software, it will lock or delete your downloaded files.

Moreover, it is safer to browse without history. To protect your downloaded files, keep separate folder rather default folder under user directory. If you want to download files that may break the stream, use other third party program like free download manager or else. It allows you resume your downloads without losing the bandwidth.

My antivirus software (Avast Pro) is set to not do anything without asking me first, so I very much doubt that it deletes the files. Malware? Very much doubt that too. I have a very clean windows installation with just the bare work necessities.

The initial problem – the failed download – may be caused by a write permission conflict between Firefox, Avast and Dropbox. There is a lot going on when they download (download, scan, sync), so the three programs may be arguing between themselves.

But i am absolutely certain (ok, 98% certain) that the file deletion is caused by Firefox. Simply because it only happens when I start Firefox, and it happens every time I start Firefox. It doesn't happen when I download in Chrome, even if the first download attempt fails.

The attached image hopefully describes the problem better:

Hello,

This is a bug from Firefox, not from another software. Here is the problem (As far as I can tell as a user) : 1. When a download fails, firefox automatically start the download again at the next Firefox start. 2. If a file with the same name than the failed download already exist in the download folder, firefox will delete this file (if not locked by another program) at the next Firefox start and then start the failed download again. No way to get the delete file again !

This can be annoying. Solution would be either to not delete any file but rather rename the 2nd file with (1) or (2)... As it is already doing in some other cases. And/Or make the auto download on restart for failed download optional.

I hope that I was clear.

Thx anyway to the dev !

Teflon1: Thanks for describing the problem more accurately than I did. And thanks for confirming that it actually exists.

Then the question is: Are the FF team aware of this bug, and are they doing anything to fix it?

I have a similar issue that I was able to somewhat resolve. I was able to trigger the issue with the following:

1. Start a download. 2. Open the file with the .part extension, locking the file. 3. The download will have a failed status in firefox when it completes. 4. Close firefox. 5. Close the other program that locked the file. 6. Remove the .part file. 7. Open firefox.

The download will then start again.

Note: This happens when using windows OS. I suspect it wouldn't be an issue on MAC/Linux.

I've only experienced this issue with recent versions of firefox (from around the time they removed the separate downloads window). The solution in my case was to remember to clear the download list or remove the failed downloads prior to closing the browser.

It would be nice if firefox didn't try to resume a download that failed during the renaming of the .part file - or it could just rename the .part file without downloading again.