The download link for libpng16, which is used during the installation of Carla 0.9.16, needs to be updated.

[Chinese-Coding]

Hi everyone, I ran into an issue while installing CARLA 0.9.16.

In the original Util/BuildTools/Setup.sh, libpng is downloaded using:

https://sourceforge.net/projects/libpng/files/libpng16/${LIBPNG_VERSION}/libpng-${LIBPNG_VERSION}.tar.xz

For LIBPNG_VERSION=1.6.37, this now returns 404 Not Found.

Setup.sh: Retrieving libpng.
--2026-05-09 10:26:31--  https://sourceforge.net/projects/libpng/files/libpng16/1.6.37/libpng-1.6.37.tar.xz
Connecting to 10.29.182.87:7890... connected.
Proxy request sent, awaiting response... 404 Not Found
2026-05-09 10:26:32 ERROR 404: Not Found.

make: *** [Util/BuildTools/Linux.mk:142: setup] Error 8

It looks like this version was moved under older-releases.
The working URL is:

https://sourceforge.net/projects/libpng/files/libpng16/older-releases/1.6.37/libpng-1.6.37.tar.xz

So if you're installing CARLA 0.9.16 and see a libpng download error, please update the LIBPNG_REPO path in Setup.sh accordingly.

Hope this saves someone some time.

[JArmandoAnaya]

This issue is already resolved in the current ue4-dev branch. You need to pull from the latest changes on it to build the project locally. If this resolves the issue, please feel free to close this discussion.