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I have a 2GB RAR file that contains a 9GB video file. I'm using a FAT32 file system. Now I want to unzip that file but after 4GB I get an error due to the FAT32 file size limit.

Now I want to know that how I can extract that video? I know that one way is to convert my partition to NTFS but I don't want to follow that way.

I've also tried 7-zip but that again gives error after 4GB.

One other way is to split that file but I don't know how I can split a video file that is zipped.

So any idea please? How can I get rid of this problem.


For all those who think that it is not AVI File, or may be I'm misunderstanding it, or may be I'm not mentioning correct size or if they think that it is not possible to compress that much, I'm attaching image of that file. I hope it answers all those questions.

enter image description here

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I have to ask - why not switch to NTFS? FAT32 is an ancient and outdated file system. –  Simon Sheehan Sep 10 '12 at 11:14
You can convert from Fat32 to NTFS in place but if anything goes wrong then too bad => restore from backup. So you would need a spare 160gb to back up to. sevenforums.com/tutorials/… –  ta.speot.is Sep 10 '12 at 11:33
@Kashif: I am curious as to what video format you are using that is so inefficient that RAR compression can eliminate over 75% of the data. –  James Sep 10 '12 at 11:41
The easiest, cheapest and safest solution may be a 16 GB USB stick. –  MSalters Sep 10 '12 at 12:40
10 min. Screencast? Why not reencode while unzipping? Like: unrar.exe p -inul bigCast.rar | ffmpeg -i - -acodec libvorbis -ab 128k -ac 2 -vcodec libx264 -preset slow -crf 22 -threads 0 our-final-product.mkv –  Rekin Sep 10 '12 at 15:38
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9 Answers

up vote 52 down vote accepted

There is no way you can go over the 4GB limit of the FAT32 Filesystem, because FAT32 imposes this limitation by design. This file system has a natural limitation for the maximum file size it can handle, which is 4GB.

And yes, I haven't found any tool that splits the video file while unzipping it.

The solution to this if you do NOT want to convert to NTFS is:

  • Get an external drive with NTFS filesystem on it.

  • Extract your Video file there.

  • Then use a video splitting software to split it in multiple parts, and then copy those to your FAT32 filesystem.

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I'd recommend a cheap 16GB flash drive, formatted to NTFS –  Jakobud Sep 10 '12 at 16:03
Actually it is 4 GB - 1 byte (2^32 - 1 bytes). –  Mister Smith Sep 10 '12 at 16:09
@MisterSmith if you're going to be pedantic about it, technically it's 4GiB -1 byte - as 4GB is 4*10^9 bytes –  JRaymond Sep 10 '12 at 16:33
What about ramdisk instead of external HDD ? –  Marek Sebera Sep 10 '12 at 17:27
@MarekSebera It seems unlikely that a computer using FAT32 as its primary filesystem would have 9 GB of free memory.. –  Brendan Long Sep 10 '12 at 17:37
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You can try to play the RAR (sic!) file with VLC media player. It does have internal support for RAR. This would only work if your RAR is not encrypted. I do not know the internals of VLC's implementation but I think VLC does not create temporary files, then this might work.
EDIT2: will not work with compressed archives, but should work with multi-volume RARs.

But if you want access the real file and playing it is not enough: Mount the RAR file with WinMount http://www.winmount.com as a virtual drive.
EDIT2: Does not work, stops after about 4GB (tested by asker)

OK I just remebered that Microsoft Virtual PC can do multi-volume VHDs on FAT32. Related: http://www.k2underground.com/blogs/blacktop/archive/2009/06/26/microsoft-virtual-pc-and-fat32-disks.aspx
Just keep in mind that you cannot use these VHDs without MS Virtual PC. To use or open them with other software they have to be joined first. Its a little overkill just to open a file but you might try it. I have however not tested this on my new Windows 7 PC only on my older PC with WinXP.

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If this works, this is by far the best answer for the given problem. –  hydroparadise Sep 10 '12 at 17:18
A few other things to try: v12pwr.com/RARFileSource and shapeshifter.se/code/vlc-unrar . I've had success with native VLC unrar, vlc-unrar and rar file source. rar file source is by far the highest successrate, in my experience. –  user606723 Sep 10 '12 at 17:29
Actually, most of these options will not work if the rar archive is compressed, afaik. –  user606723 Sep 10 '12 at 17:32
Winmount has same problem... it gives error when done with half of file( around 4 gb) –  Kashif Sep 10 '12 at 21:19
Isaac: but VLC can open the (2GB) RAR file? –  Konerak Sep 11 '12 at 9:50
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You can boot a linux live distribution and mount your file system. Then run

7z -so e file.rar | split -b 3500M

That way you end up with the split file video on your FAT partition. I have no clue if any player is able to actually display the file.

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hmm, you might have better luck converting it into 3 movie files with a suitable tool maybe? –  Journeyman Geek Sep 10 '12 at 12:16
True. Instead of split you could pipe it through ffmpeg. But that's not within the scope of this question. This answer should show an alternative way which does not involve resorting to NTFS. The OP is responsible for doing something useful with the split files. –  Marco Sep 10 '12 at 12:21
I doubt there is any reason you can't just do this on Windows. gnuwin32.sourceforge.net/packages/coreutils.htm –  user606723 Sep 10 '12 at 19:46
I think installing split on windows is probably going to be the simplest option, as far as just splitting the file goes. Some of the better video players (VLC) might be able to handle the split video files. –  nynexman4464 Sep 10 '12 at 20:05
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10 min. Screencast? It's probably badly encoded (or maybe even not at all).

Why not reencode while unzipping? It won't require external drive. For 10 min. you could possibly end up with a file of around 100mb in size.

Assuming Windows Command Line you could try:

unrar.exe p -inul bigCast.rar |   ^
 ffmpeg -i -                      ^
 -acodec libvorbis -ab 128k -ac 2 ^
 -vcodec libx264                  ^
 -preset slow -crf 22             ^
 -threads 0 smallCast.mkv 

The unrar p instructs rar to print the content to STDOUT. Than it's read back by FFmpeg -i -. The ^ characters are line break escape characters from Windows .bat file format.

You can get FFmpeg from Zeranoe FFmpeg Builds site. For simplicity pick the static one.

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it didn't work properly. i just got one clip of 1:08 minute. and when i run it, its just a few seconds clip. –  Kashif Sep 11 '12 at 9:54
clever idea and I'm sure that it could be worked out by using correct ffmpeg params (if you have time to discover them) –  ssg Sep 11 '12 at 11:11
There's a flaw possibly - the file to extracted should be specified somewhere. I'll look into it yet –  Rekin Sep 11 '12 at 11:22
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FAT32 does not support files larger than 4 GB, so you can't create files larger than that on any FAT32 filesystem. Which operating system do you use? On Windows you can convert FAT32 to NTFS on the fly by using convert.exe (replace D: with your actual drive letter):

convert D: /fs:ntfs

Edit: Quoting from the aforementioned MSKB article about convert.exe:

Note Although the chance of corruption or data loss during the conversion is minimal, we recommend that you perform a backup of the data on the volume that you want to convert before you start the conversion.

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Remember to always make a backup before you do this kind of stuff. –  Baarn Sep 10 '12 at 11:42
I'm using Win7. but if i use convert then it will format my whole partition. and this is not what i want. –  Kashif Sep 10 '12 at 11:46
Using the convert tool does not erase its contents. But it's a matter of good practice to keep a backup anyway. –  PhonicUK Sep 10 '12 at 12:54
@Kashif why would you want to use FAT32 with win7? NTFS is a far better file system both in support for large files as well as security and stability (less issues with data corruption). –  AlanBarber Sep 10 '12 at 18:09
I'm astonished Windows 7 even lets you have a FAT32 system partition. –  Alan B Sep 11 '12 at 8:49
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You could use Partition Magic, which allows you to repartition drives without destroying data, so you create a 12gb ntfs partition, unzip your file then recode it with ffmpeg or another recoding tool back to your fat32 partition then return the 12gb working partition to the fat32 drive... long winded, but should work

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It's completely impossible to create a file larger than 4GB in a FAT32 volume. The only way to solve your problem is

  1. convert your partition format to exFAT or NTFS or some other format which support large file
  2. treat your rar file as a stream -- this maybe possible in theory but I don't know any implementation of this.
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I wonder why exFAT isn't among more answers. The question really is if Microsoft has support to do an inplace upgrade of from FAT32 to exFAT. –  Nathan Adams Sep 12 '12 at 4:01
exFAT is property and less support. Of course M$ recommend us to upgrade to exFAT for removable storage such as Flash Drive and SD card to avoid the loss caused by NTFS's journal feature, but it's not only a new version of FAT32 -- it's nearly a whole new file system. During the years FAT32 widely used, almost every devices and programmes are support it. However, exFAT is only known to be support in Windows XP SP1 later, and in UNIX-like system, only Mac OS X and a Fuse implementation are known to be supported it. –  Lingfeng Xiong Sep 12 '12 at 6:18
FWIW, here's where to download Microsoft's exFAT file system driver update package for 32- and 64-bit versions of Windows XP and Windows Server 2003. It supports theoretical maximum volume and files sizes of up to 64 ZB (that's right, ZettaBytes, which are 1 billion TeraBytes each). –  martineau Sep 16 '12 at 17:22
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The best nd only answer is no. you cannot, reason -->the creator of FAT32 filesystem have implemented that limitation on the maximum size of file it can handle(4GB).

Though many of users have answered it before, the only thing i can add is that means other than converting your drive to NTFS or copying that file to a pen drive formatted in NTFS system nd then extracting, cannot work, because it is the OS that keeps the data in temporary files/locations/folders for temporary purpose, which cannot again cross the 4GB limit.

Easiest way is to buy a pen drive and uncompress your data on it.

Resource :- Extensive experience with Windows OS's

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please tone down your usage of bold format, there's no need to go overboard. It doesn't enhance your post –  Sathya Sep 11 '12 at 4:13
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You can convert your FAT32 to NTFS without loosing your data by the following methods for your 4gb transfer

On Windows,

  • click Start --> Run
  • type in cmd
  • then type convert c: /fs:ntfs (depending on your drive name, in my case C:)

For this to run you need to unmount the disk which you want to convert. For this just reboot the computer and do nothing else other than try to convert the file system. If you still get that error, reboot into safe mode and do it again. The conversion doesn't actually happen right then. It will reboot the computer and then run the conversion process before the OS proper loads.

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