So I'm at the final part of the game. During the final 2 or 3 cutscenes (the pre-rendered,NOT ingame), I get the error "unknown fatal exception" and the game crashes. I can skip them and continue without problems but still...
I find it weird that it didn't happen in any of the previous cutscenes.

What OS are you running? If its vista or win7 are you running as admin? Also you say its the pre-rendered cut scenes are there any other pre-rendered cutscenes in the game that worked fine?(Have not had the chance to play this game myself yet)

I use XP and I only see the file mpeg2data.ax.
However since it's a known problem as I see in your site I'll mark your post as the solution.
I cannot test it right now because I finished the game and didn't keep any saves. Also it is random. It may or may not happen and at random times in the cut-scene.
Thanks!

I'm getting this problem too. I'm running Windows XP (SP3) and I don't have a file called mpeg2dmx.ax anywhere on my computer - I searched. The nearest named file is mpeg2data.ax, and renaming that didn't stop the error happening. You suggested that other codecs might be causing the problem - how do I know what codecs are installed and how can I remove them to test this?

I'm running with Windows 7 and have the same problem, I also can't rename the files you talk about, so what should I do?

Renaming that file and all other.ax files in that directory don't work. I had done that and the cutscene at the end of day2 7-10 still crashed game. Checking system32 directory after that showed that the original files just replicated themselves so I had the .ax files and the ones I renamed to .bak.
It'll play the first few seconds of the scene, then crash. Exiting out of the scene before it crashes helps.
The files for the cutscene are in Gabriel Knight 3/Data, listed as 207aend, etc. If you can't play them directly by clicking on the file, go here:
http://www.radgametools.com/
and click on bink video link. Download and install it. Now you should be able to play the cutscenes directly by clicking on the files.

I just had the same issue in Day 2. I don't have the .ax file indicated in the earlier solution (with Win7 x64) but it's easy enough to play the bik files using the RAD video tools, so I went that route. Takes me out of the game for a moment, but it's the first crash, and I save often enough, I think. At least I can skip the scene but still get the idea of what it contained. Good suggestion. :)

For the non-tech, I had the same problem at Day 2 between 7-10 and 10-12. Running Windows 7. Had read about this and suggestion was to skip cutscene. Yes that works but since there isn't an option to "skip cutscene" I just kept left clicking and actually managed to see all of the cutscene and also continue with game. Agree with others that this should be fixed and good GOG, let us know when it is so we can "reload". As you can see, I'm not a techie, just an avid player. If there are others like me, try just repeately left clicking when the cutscene begins. In my case, I ended up seeing it in its entirety and also moved forward in the game. Update that worked at that point. Another crash at Day 2 12-2pm. Then had to use ESC key to entirely skip cutscene.

I'd say this problem is far from solved. I'm running Windows 7 and had the "unrecognized fatal exception" error occur during several of the cutscenes. Sure, skipping them is a way to let the game move forward, but it's hardly ideal. I've tried a few things, such as changing the resolution, but in most cases nothing worked. The last straw was the very final cutscene, which pretty much wrecks the entire experience, having to skip it. You might as well skip the whole story. If anybody has a real solutions to this, I hope it will be posted here.

Still the same issue. Using 64-bit Win 7. It really ruins the game, when the ending (along with at least two important cutscenes) has to be watched from Youtube. I hope GOG would respect this masterpiece by fixing the issue with the videos. The CD version didn't have the problem that the GOG version has. And no, this hasn't been SOLVED.

Having the same problem as everyone else, under the same circumstances. The file I need to rename doesn't exist and Collector's batch file doesn't solve anything. After getting really immersed in the game, having to sift through a bunch of ambiguously-titled files in the GK3 data folder to see a cutscene completely kills the mood. This problem is NOT solved.

I have the same problem, I also tried the things that other people suggested but it didn't work!

I use win 7 and cant see the cutscenes.
its an important part of the game. it seems this problem is well known but Gog doesn't earn about it
and that not ok

I'll post my two cents here. I am also running Windows 7, 64-bit, and I ran into the "unknown fatal exception" error on the cut scene that ends a time block on Day 2.

I was able to get around it by moving two files out of the Windows/System32 folder. The two files are:

Mpeg2Data.ax
mpg2splt.ax

I just moved them temporarily, ran the game, and the cut scene had no issues. Afterwards, I moved them back.

UPDATE: Okay, so it was only a partial solution. It worked for the one cutscene, but then the error occurred again with a cutscene from Day 3 AND, even worse, it happened with the ending as well. I had to resort to watching the videos on YouTube...