I've been using this tutorial to do a Sims 4 to Sims 2 conversion. https://vulrien-sims.tumblr.com/pos...othing-tutorial

Everything went fine until I tried to open the Wavefront OBJ file in Milkshape and then nothing showed up. The weird thing was that the previous conversion I'd tried to open had opened just fine, but this one wouldn't, even though I tried it twice and did exactly the same steps as with the one that worked.

Does anyone have an idea what I might have done wrong?

What kind of mesh are you converting? TS4 ingame meshes don't tend to cause any issues with exporting, but there has been issues with some CC meshes. There are a few workarounds for those, but it helps to know which meshes.

Which Blender version are you using?

Are your export settings somewhat like these? They tend to work for me with OBJ files (still not sure if all these tick boxes are needed, but it exports everything I want, and I don't get black meshes or other funky business)
https://i.postimg.cc/d0bRhWRH/Screenshot-New-159a.jpg

This is the mesh that I had no problems with.

https://www.ebonix.com/single-post/ebonix-khalid-dreads

And this is the mesh that won't work (Reply 2).

http://www.theblacksimmer.com/downl...as-2017-127876/

I tried using the same export settings as yours, but it still didn't work.

I tried the most recent version of Blender, but Sims 4 Studio wouldn't accept it and made me go back to version 2.79. I just tried exporting the mesh in the current version as well, but it still didn't work.

The second one requires a login (not in an account setup mood today)

Hairs can be a bit iffy - if you can get them into Blender (which is a first step, sometimes that doesn't even work, especially by some creators at TSR, as they do some strange things to their hair files), you can try to open up a new, empty Blender window, choose "append", and then choose the mesh part(s) you want from the "object" folder. They won't have a texture and not entirely sure if they're properly rigged still - but if you only need an OBJ anyway, that does the trick.

If you can't export the mesh from S4Studio, then I'm not sure. I think there are a few workarounds (someone mentioned TSRW, and the meshing toolkit, I think?
(this one: https://modthesims.info/d/481950/me...12-20-2018.html ) - but I haven't figured exactly how. I've experimented a little bit with a workaround with the binary files, but it's very fiddly and is very random whether it works or not, so I kinda just gave it up.

You can also check if the item has been merged - if so, try unmerging it.

Thanks! The append thing worked.