How Do You Open a .dmg.bz2 File (UT2004 Demo)?


I recently downloaded the demo version of Unreal Tournament 2004 for my OS 10.3.9, and when I looked at the file, it's extension was in the dmg format, but with a .bz2 at the end (it looks like: filename.dmg.bz2). How would you open such a file? My computer won't automatically open it because there is no program associated with such an extension. Your help is appreciated. Thanks in advance.


You need to unstuff it with StuffIt Expander, then mount the resulting DMG file by simply double clicking on it.


Tech-Bot 5000
You also might have to remove the ".dz2" from the file name because .dmg is what the mac identifies as a compressed archive file.


U.S.D.A. Prime
bz2 is bzip compression. Removing it from the filename won't do anything -- except remove those characters from the filename.

You need StuffIt Expander, as mentioned by MBHockey, which is free from


Tech-Bot 5000
Right, but the post says his computer can't automatically open the file. Since there are two extensions on the file, the .dmg and the .dz2 then removing the .dz2 will tell his computer the file is compressed and will then automatically open the file.

Or he could get info on the file and select "open with" for stuffit expander.

So removing the file name WILL do something, thank you very much. :)


Digital Music Pimp
um. if you rename a file called to xyz, it DOES NOT remove the extension. it sets the file to hide the extension. and a DMG is NOT a compressed archive, it is a disk image.


Tech-Bot 5000
The file name is this: filename.dmg.bz2 and I only suggest removing the last extension. Removing the extra extension in name alone could make the file be recognizable by the computer as a disk image (pardone moi).

My post also stated you could force the computer to open the .dmg file with stuffit expander, which more than adequately answers the question.


U.S.D.A. Prime
...but it's not a disk image. It's a disk image inside of a bzipped archive. You must first remove the bzip compression, and only then will you have a .dmg file. The only way to remove bzip2 compression is to uncompress it. Removing the file extension does not accomplish this.

Think of it as "reading right-to-left." If you have a file named, you need to work from the right to the left -- first, you need to "unzip" the file (.zip), then you need to "unstuff" the file (.sit), then you need to un-b-zip the file (.bz2) then you will be left with a .dmg file. There's more than one compression to this file, as indicated by the multiple extensions.

Removing the extension, hidden or not, will not make the archive any easier to open. The most you will accomplish is fooling the computer into thinking that it's a straight .dmg file, but when it tries to open it, it will fail -- because it's still bzipped. The process that mounts/opens DMGs does not understand bzip compression, and, as such, will not be able to open the .dmg file -- because it's not a .dmg file. It's a bzipped .dmg file.

I fully understand your logic, Nato, but it will just not work in this situation. The bzip compression must be removed before the file will become a .dmg file.

You must uncompress the bzip file first -- there is absolutely no way around it. StuffIt Expander is the way to go with this, but it's not the only way to go.

Do this:
1) Open Terminal.
2) Type "bzip2 -d " exactly like that, without the quotes. Note the trailing space at the end.
3) Drag-and-drop the .dmg.bz2 file into the Terminal window. The path should be filled in automatically.
4) Hit enter. The file should be decompressed, leaving you with a straight .dmg file.
5) Double-click the .dmg file to mount it.


Ok this post is old but thought I'd share anyway.
I removed the .bz2 extension as Natobasso suggested, that did the trick then I could mount the image by double clicking, thanks.