Unable to locate package 🐧 Linux

E: Unable to locate package (apt / apt-get install)

apt can’t find the package name in its package lists — the lists are stale, the repository isn’t enabled, or the name is wrong for this distro version.

Seen on: Linux

Meaning

apt only knows packages from the indexes downloaded by apt update. Fresh servers and Docker images ship with empty lists, so install fails until you update. Package names also differ between Ubuntu/Debian releases, and some live in universe/contrib or a third-party repo.

Common causes

  • apt update never run (fresh server / Dockerfile without update)
  • Package in a repository component not enabled (universe, multiverse, contrib)
  • Name differs on this release (python vs python3)
  • Third-party repo not added
  • Architecture-specific package

⚡ Quick fix

  1. Run sudo apt update first
  2. Search the real name: apt search <term> / apt-cache policy
  3. Enable universe: sudo add-apt-repository universe

Detailed fix by platform

Ubuntu

  1. bash
    sudo apt update
apt search nginx | head
sudo add-apt-repository universe && sudo apt update

Dockerfile

  1. RUN apt-get update && apt-get install -y --no-install-recommends curl && rm -rf /var/lib/apt/lists/*

How to diagnose

  1. Lists — When was apt update last run?
  2. Name — packages.ubuntu.com / packages.debian.org for your release
  3. Release — lsb_release -a

🔧 Still not fixed?

Many errors look alike. If the steps above didn’t solve it, one of these is probably what you’re facing:

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