# Ubuntu 24.04 complains about unknown key used for signature on apt.kitware.com ...

**URL:** https://discourse.cmake.org/t/ubuntu-24-04-complains-about-unknown-key-used-for-signature-on-apt-kitware-com/15454
**Category:** Site Feedback
**Tags:** os:linux
**Created:** [January 12, 2026, 11:57am UTC](https://discourse.cmake.org/t/ubuntu-24-04-complains-about-unknown-key-used-for-signature-on-apt-kitware-com/15454 "2026-01-12T11:57:19Z")
**Posts on this page:** 1
**Showing post:** 4

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### Author: ![exoosh](https://discourse.cmake.org/user_avatar/discourse.cmake.org/exoosh/32/4077_2.png) [@exoosh](https://discourse.cmake.org/u/exoosh)
#### Post date: [January 12, 2026, 1:48pm UTC](https://discourse.cmake.org/t/ubuntu-24-04-complains-about-unknown-key-used-for-signature-on-apt-kitware-com/15454/4 "2026-01-12T13:48:01Z")

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`deb [arch=amd64 signed-by=/usr/share/keyrings/kitware-archive-keyring.asc] ...` was the issue. The file created by current versions of the upstream script and the instructions shown on [apt.kitware.com](http://apt.kitware.com) are `.gpg`, not `.asc`.

Or in other words: apologies for the noise.

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_[View the full topic](https://discourse.cmake.org/t/ubuntu-24-04-complains-about-unknown-key-used-for-signature-on-apt-kitware-com/15454)._