Today while starting up JDownloader I noticed a strange behavior. The program prompted to pick a language first, and then showed up with an empty download queue. That was unfortunate since I had some downloads left in the queue from the other day.

I first thought that I had just installed a second instance of JDownloader, but discovered a moment later that the new installation seemed to have overwritten the database file containing the file download queue.

I knew that JDownloader was creating backups of the database in regular intervals. I checked the backup folder of the JDownloader program folder to find out that the program had saved more than a dozen database backups in the past months.

This was interesting in itself as it can be seen as a privacy issue by some users as it is possible to restore the download queue with the help of the backups.

The last database backup file is database.zip. To restore it you need to do the following. Quit the JDownloader program. Make sure it is completely terminated and not sitting minimized in the system tray.

Open the database.zip file and extract the contents (database.properties and database.script) to the main JDownloader/config/ directory. Replace the two database files listed there.

This restores the download queue. You may still be missing a few downloads though depending on the time and day the last backup was created by the file downloader. In my case, the last backup had been created four days ago which meant that I lost a few file downloads that I added after that date.

Actually, two situations can turn up at that moment:

1) Listing the contents of a particular website is permitted and you can simply paste the path to a download manager which should be able to manage downloading the files. Though, it’s not very common.
2) Listing the contents is prohibited and your download manager probably won’t be able to manage downloading the files. You’re not gonna download the files one at a time, are you?

Since in my case a “Access denied” message appeared, my download manager was unable to download contents of the website and I had to find another way. I couldn’t remember any Windows’ built-in utility that could do that job for me so that I checked the net and found a nice tool that can download files from the command-line. File Downloader [via Softpedia] is a useful tool working in command-line mode, able to download files with several parameters. Now, this tool wouldn’t be of much use if we didn’t combine it with the power of command-line itself, right?

That’s when creating loops with the “for” statement comes in handy again. Meeting the two requirements:

• base path of desired files remains the same for each file
• each file is (sequentially) designated with a number

we continue our effort-saving journey. To download those multiple files from a single source, fire up your Command Line Interface and set the working directory to File Dowloader’s home folder. Here we can start the loop with proper parameters:

for /L %i in (#,1,#) do download http://web.site.net/Podcast%i.mp3
the first # represents the number included in first filename
the second # represents the number included in last filename
replace this example URL with the real one, %i substitutes number in filename

Here we go. Hit Enter, sit back and watch File Downloader do that time-consuming process for you. I’ve just finished downloading 329 podcasts for my mp3 player w/o a single mouse click which saved me more than enough time to write this article ;)