Problem installing via brew on macOS 26.3

[chrisstuartparry]

Hi,

I'm running into an error when trying to install via Homebrew.

Here's my terminal output:

╰─ brew install --cask iguanatexmac latexit-metadata
==> Would install 2 casks:
tsung-ju/iguanatexmac/iguanatexmac tsung-ju/iguanatexmac/latexit-metadata

==> Fetching downloads for: tsung-ju/iguanatexmac/iguanatexmac and tsung-ju/iguanatexmac/latexit-metadata
✔︎ Cask latexit-metadata (1.0)                                                                                                                                                           Verified     97.4KB/ 97.4KB
✔︎ Cask iguanatexmac (1.62.1)                                                                                                                                                            Downloaded  854.4KB/854.4KB
==> Installing Cask iguanatexmac
==> Moving Generic Artifact 'IguanaTex_v1_62_1.ppam' to '/Users/[user]/Library/Group Containers/UBF8T346G9.Office/User Content.localized/Add-Ins.localized/IguanaTex_v1_62_1.ppam'
==> Moving Generic Artifact 'IguanaTex.scpt' to '/Users/[user]/Library/Application Scripts/com.microsoft.Powerpoint/IguanaTex.scpt'
==> Moving Generic Artifact 'libIguanaTexHelper.dylib' to '/Library/Application Support/Microsoft/Office365/User Content.localized/Add-Ins.localized/libIguanaTexHelper.dylib'
sudo: sorry, you are not allowed to preserve the environment
==> Backing up Generic Artifact 'IguanaTex.scpt' to '/opt/homebrew/Caskroom/iguanatexmac/1.62.1/IguanaTex.scpt'
==> Removing Generic Artifact '/Users/[user]/Library/Application Scripts/com.microsoft.Powerpoint/IguanaTex.scpt'
==> Backing up Generic Artifact 'IguanaTex_v1_62_1.ppam' to '/opt/homebrew/Caskroom/iguanatexmac/1.62.1/IguanaTex_v1_62_1.ppam'
==> Removing Generic Artifact '/Users/[user]/Library/Group Containers/UBF8T346G9.Office/User Content.localized/Add-Ins.localized/IguanaTex_v1_62_1.ppam'
==> Purging files for version 1.62.1 of Cask iguanatexmac
Error: Failure while executing; `/usr/bin/sudo -E -- /bin/cp -pR /opt/homebrew/Caskroom/iguanatexmac/1.62.1/libIguanaTexHelper.dylib /Library/Application\ Support/Microsoft/Office365/User\ Content.localized/Add-Ins.localized/libIguanaTexHelper.dylib` exited with 1. Here's the output:
sudo: sorry, you are not allowed to preserve the environment

though do note that I've removed some (irrelevant) brew warnings about other taps I have being untrusted, for brevity and digital footprint reasons; I mention it here on the off chance it somehow matters. I also replaced my user directory with [user], though just for the window here, obviously.

I have macOS 26.3, and am using Homebrew version 6.0.15, and the device itself is a 2021 MacBook Pro M1 Pro.
I made sure to (as is now necessary with Homebrew v6.0+) trust the tsung-ju/iguanatexmac tap and the specific cask tsung-ju/iguanatexmac/iguanatexmac.

I'll try installing manually after submitting this issue, and will add a note here if that doesn't work either (though I imagine it will).

[Jonathan-LeRoux]

Thanks for the detailed report. Based on a discussion with ChatGPT, this looks like a restriction in your Mac’s sudo configuration rather than a problem downloading or trusting the cask.
The installation fails when Homebrew tries to copy libIguanaTexHelper.dylib into the system-wide Microsoft Office add-ins directory. Homebrew chooses to run that copy using sudo -E because it's a privileged installation, but your system does not permit callers to preserve their environment, likely because you have an organization-managed Mac, or customized /etc/sudoers policies.
It doesn't look like there is an easy fix to make the homebrew installation work in such cases, so I'd suggest just using the manual installation. Changing the sudo policy may also resolve the Homebrew installation, but on a managed device that would need to be handled by your IT administrator.