MP42 Decompressor for VirtualDub

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04-08-2004 08:46 PM

I’m trying to edit .avi video file using VirtualDub, but everytime I try to load the file, I get message “Cannot locate decompressor for format MP42..."
I checked various places and installed alot of codecs I found but still not working. I installed codecs I found on Microsoft website, FFDshow, Divx, mpeg4x, all-in-one pack, etc etc.
Does anyone know exactly what I should install?
I’m using Windows XP.

thanks. reply


08-22-2004 04:16 AM
Another Anaoymous

I had the same problem. A quick Google search cam up with this website

I installed downloaded and installed the codec headed “nAVI video codec - vids:nAVI, MP4, MP42, MP43 decompressors”.

And VirtualDub now works fine, as does Boilsoft AVI joiner

Hope this helps someone reply


06-06-2006 04:01 PM
Anonymous Aardvark

Thanks, the nAVI codec solved my problem perfectly, thanks! reply


01-11-2007 10:59 PM

I want to decode MP42 compressed .avi files and extract each frames using C++. Any pointers?
Thanks. reply


09-28-2007 06:43 AM

worked perfek


p reply


12-17-2007 05:24 PM

The russian site with the nAVI codec contains spyware... reply


12-23-2007 03:26 AM
1,580 posts

If anyone else is having trouble with MP42 MPG4 or MP43 in VirtualDub: the newer versions of the decoders released by Microsoft are DirectShow-only. has an older version that is VfW-compatible. If you get a warning about overwriting an older version or lack of digital signature (the old versions didn’t have them I don’t think), just click continue. reply


01-13-2008 02:28 PM

Warner wrote:
The russian site with the nAVI codec contains spyware...

Hi Warner

Works for me.

I cannot find spyware code with Etheral, Mcafee, Adaware or looking in the file!
Why do you assume this? reply


02-02-2008 09:55 PM

You can also get the nAVI codec @ under “Mpeg4 Codec - FOURCC: nAVI” (I found it to be a lot less confusing than the Russian site). reply


03-25-2008 04:14 PM

The last listed nAVI file here is the same as the first and neither work for me. Another site listed here has sql server problems, but I’m sure its pkg is no different. I tried installing them both “active” and normal. Sherlock says I have it already, but neither VirtualDub nor Video Inspector can find it. I tried re-booting too. reply


03-25-2008 04:55 PM

Remembering that I tried the pkg from only as an active install, I tried one more time as only “install” and this time it worked, and VD opened the files. I converted some flv’s with Media Converter SA Edition using default settings and it made them mp42 which play fine in WMP, etc but I wanted to join them. reply


06-08-2008 05:54 PM

Just to confirm that the codec obtained from
solved my V Dub MP42 problem. Saved me risking a Russian site ;-) Thanks... reply


01-05-2010 10:41 PM

Had this same problem with latest 64bit v. of Vdub.
was about to go install all these codecs/etc. but just re-booted my machine instead. That did not help.
However, VirtualDub V. 1.9.4 will open all my mpeg4 and other formats just fine. Only Vdub V.1.9.8 64bit will NOT open them.

No idea why... but just to let you know you may not need to go visiting iffy sites.
Also, you can try downloading the mpeg4 pack here as well:
It appears more reputable, but I did not install it, so can not vouch for it. reply


01-06-2010 08:35 PM
1,580 posts

If you’re using the old MS MPEG-4 codecs, use them with the 32-bit version of VirtualDub (yes, 32-bit VirtualDub works fine with 64-bit Windows).
If you’re using 64-bit VirtualDub, you need 64-bit VfW decoders. ATM the only one for MP42 I know of is bundled in the 64-bit version of ffdshow-tryouts. It’s still experimental.
Of course, check the VfW box during setup. To minimize the chances of problems, I’d suggest disabling the decoding of all other codecs (during install there’s a box that lets you choose which codecs ffdshow should decode - uncheck them all). When you’re done, find ffdshow in your start menu and run the vfw configuration (or do it from the box at the end of setup). go to the DEcoder tab. Under MP42, set it to libavcodec. remember to click apply. reply


09-09-2010 11:59 PM

Thanks dude it works !! reply


09-13-2010 02:47 AM

Thanks Anonymous - the ffdshow thing worked for me too! reply


10-26-2010 07:14 PM

TNX man works perfectly reply


05-04-2011 11:34 PM

KYAHHHHHHHHH! Thank youuuuuuuuu!!!!!! It has really fixed my problem!!!!!!!! Thanks!!!!!!!!!!!!!!! reply


06-24-2011 04:48 PM

install (any video converter)

try it and see reply


10-11-2011 01:12 PM

When I click on to download the decompressor (below the line:

“nAVI video codec - vids:nAVI, MP4, MP42, MP43 decompressors”

I come to a site with nothing on it...



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