Problem with Zarx264gui...

[8bit_samurai]

Have you tried adding

ConverttoYV12()

to the script? I kinda had the the same problem, though I don't remember if it was the same error.

[kmv]

"The format is not supported. (Error=80040265)"

That error is actually coming from Windows, not Zarx264gui. There are several possibly causes (listed in order of most likely):

1. A codec needed for the AVI is not installed. You mention AAC (and Nero) but you don't mention the video codec.
2. The codec is installed, but hasn't been correctly registered. This can happen, and doing an uninstall then reinstall may or may not help. A codec registration tool will help here, unfortunately it's been a while since I have been on Windows and can't remember the one I used to use. It might have been GSpot. Also going for a codec pack like CCCP might help.
3. You have a codec clash - more than one installed codec is attempting to wok with the stream. The resolution is the same as in the previous point.
4. The FourCC in the AVI file itself is bad and is requesting a non-existent codec. This may indicate a corrupt AVI or a broken encode. Use a FourCC changer to check and fix.

[kmv]

5. It's not actually an AVI file. It is something else (an ASF perhaps) that has been incorrectly named.

[SheeGee]

i also have a problem with zarx264

i even got the debugged one.

when i input an .avi file i get an error that says "external component has thrown an exeption"

[JaddziaDax]

you are supposed to import your video through an avisynth script..

[SheeGee]

but the new one had the option of inputting avi.

i did try with the avs but same thing happened..

[Zarxrax]

That error sounds like it is probably coming from windows.
I have been working on Zarx264gui some today, so I might have a new version posted in the next week or so. There's a chance it might fix the problem.

Otherwise just encode the old fashioned way with the command line. If you go in the advanced tab, you can click on create bat, which creates a batch file containing all of the command line arguments used to encode the video.