If you cancel an unfinished download then the already saved part is removed, even if you paused it before.
You will have to make a backup copy of the partial file elsewhere if you want to keep it.
Otherwise you need to use an external download manager to download the files.
The Firefox download manager is very simple and doesn't have the extra features that other download managers have.

Hi, in mozilla version 3.6.x it saved files with equal names as indexed so A, A(1), A(2) and etc. It is recommended that the new versions keeps good operation else new version why new version? Thanks

Hi, in mozilla firefox older versions(2.x,3.x) it saved files with equal names as indexed so A, A(1), A(2) and etc. It is recommended that the new versions keeps good operation else new version why new version? Thanks

If the file names as send by the server are the same and you have configured not to ask where to save each file then this still should happen.

• Tools > Options > General : Downloads : "Save Files to"

Current Firefox versions remember the download directory based upon the URL, so if the URL changes then the default folder may be chosen if there hasn't been selected a download folder before for that server.

Firefox 11+ versions have support via browser.download.lastDir.savePerSite pref to disable to disable the feature to remember the download directory based upon the URL.

The browser.download.lastDir.savePerSite pref doesn't exist by default (it is hidden).

Create a new Boolean pref with the name browser.download.lastDir.savePerSite and set the value to false.

• http://kb.mozillazine.org/about:config

You may have the clear the "Site Preferences" via Clear Recent History to remove already stored data.

Hi, thank you for reply, but I means all of default users may lose files because of bad decision on downloads, default was indexing and change it is bad, if I could edit source of 13 I will enable it and then use it else I will remove firefox 13 and reinstall firefox 3.6.28 because I lose my time and data with this bad choice. I want to say to mozilla team this is very very bad implementation to new versions. Thanks