Using codecs without installing codec packs

[aax]

Is it possible to use codecs without messing up my PC by installing a codec pack? Something similar to how filters are loaded through .dll's.

Currently I use MPC for playback so I don't have anything installed, and I usually just encode DVDs, for which I only need DGIndex, but now I have this XviD video that I need to load.

[Reel.Deel]

Use FFMS2 (http://avisynth.nl/index.php/FFmpegSource) or LSMASHSource (http://avisynth.nl/index.php/LSMASHSource).

[aax]

Hmm, they don't seem to work.
Smash gives error 0x7e, and with FFmpegsource it can't locate decompressor.
I only loaded their dll's; am I doing it wrong?

[StainlessS]

Point this at dll to find out what runtimes it needs (error 0x7e)
http://www.dependencywalker.com/

[Reel.Deel]

Smash gives error 0x7e

The wiki page notes that one of the requirements is the Microsoft Visual C++ 2013 Redistributable Package (vcredist_x86.exe) (http://www.microsoft.com/en-us/download/details.aspx?id=40784). And also make sure you downloaded the 32-bit Avisynth plugin.

[aax]

Installed Microsoft Visual C++ and now it also says "couldn't locate decompressor for fourcc xvid".

And here are Dependency Walker results:
LSMASHSource (http://postimg.org/image/sr1unlovb/)
FFmpegsource (http://s15.postimg.org/m1vb7l3jf/Untitled2.png)

[StainlessS]

Google is your friend
http://superuser.com/questions/827752/run-vcredist-x86-exe-missing-msvcr120-dll

EDIT: VS 2013 as posted by Reel.Deel
http://www.microsoft.com/en-US/download/details.aspx?id=40784

[colours]

If even after following the above steps you have trouble opening the file, you should do what you should've done from the very beginning: upload your Xvid file somewhere so we can better help you out.