Paste the error you got while installing or signing in to Claude Code. We’ll explain what it means in plain English and link you to Anthropic’s official fix.
What it means: The install usually worked. Your terminal just doesn’t know which folder the new program is in yet, because the window you installed from still has the old settings.
What to do: Close the terminal and open a new window, then try again. If it still can’t find Claude, the install folder needs to be added to your PATH. Follow Anthropic’s step-by-step PATH fix for your system.
What it means: The install address sent back a web page, so your terminal tried to run HTML as code. This happens with regional blocks, some networks and proxies, or a temporary outage.
What to do: If the page mentioned “App unavailable in region,” Claude Code isn’t available in your country. Otherwise, try a different network, or use one of the alternative install methods Anthropic lists.
What it means: The server refused the download. Common causes are being in an unsupported country, or a company firewall or proxy blocking it.
What to do: Check you’re in a supported country, then check your network with IT if you’re on a work connection. Anthropic’s page covers network checks and alternative installers.
What it means: The install script didn’t arrive in full, usually because the connection dropped.
What to do: Try again on a stable connection. If it keeps happening, Anthropic’s page shows how to test the connection and lists other install methods.
What it means: Linux stopped the installer because the machine didn’t have enough free memory. Claude Code needs at least 4 GB of RAM.
What to do: Close other programs or use a machine with more memory, then try again. Anthropic’s page explains adding swap space on small servers.
What it means: The installer was run somewhere that isn’t a normal interactive terminal.
What to do: Run the installer again from a regular terminal window. Anthropic’s page has the details.
What it means: The installer tried to write to a folder your user account isn’t allowed to change. This is most common with the npm install method.
What to do: Don’t try to force it with administrator rights. Anthropic recommends fixing the folder’s permissions or switching to the native installer instead.
What it means: Your computer couldn’t verify the download’s security certificate. This usually happens on company networks that inspect traffic, or on systems with outdated certificates.
What to do: On a work network, ask IT for the company certificate setup. Otherwise, update your system. Anthropic’s page has the specifics.
What it means: Your network or a proxy is blocking the connection to Anthropic’s download servers.
What to do: Try another network, or check proxy settings with IT. Anthropic lists exactly which addresses need to be reachable.
What it means: Windows has two command windows, PowerShell and Command Prompt (CMD), and each needs a different install command. Mac and Linux commands don’t work in either.
What to do: Check your prompt: PowerShell shows “PS” at the start, Command Prompt doesn’t. Then use the command Anthropic lists for that window.
What it means: Your copy of Homebrew’s app list is out of date, so it doesn’t know about Claude Code yet.
What to do: Update Homebrew’s list, then install again. Anthropic’s page shows how.
What it means: Claude Code needs either PowerShell or Git for Windows to run commands, and it couldn’t find either.
What to do: Anthropic’s page explains which one to install and how to point Claude Code at it.
What it means: Windows includes an older “x86” version of PowerShell. Claude Code needs the regular 64-bit one.
What to do: Open the regular “Windows PowerShell,” not the one labeled “(x86),” and try again.
What it means: Something else, often an earlier install attempt or antivirus, has the file open.
What to do: Close other terminal windows and try again. Anthropic’s page explains clearing the leftover download.
What it means: The installed version doesn’t match your Linux system’s core libraries. This is common on Alpine and other musl-based systems.
What to do: Anthropic’s page explains how to get the right build and which extra packages Alpine needs.
What it means: The installed version was built for a different kind of processor, or your CPU is missing a feature it needs.
What to do: Anthropic’s page explains how to check your processor type and get the matching build.
What it means: Recent versions have a known problem on WSL 1, the older version of Windows Subsystem for Linux.
What to do: Anthropic recommends WSL 2 where possible and explains the options on its page.
What it means: The program file changed or became unreadable while Claude Code was running. This mostly happens when home folders live on shared network storage.
What to do: Anthropic’s page explains how to install so the program stays available during a session.
What it means: The installed build isn’t compatible with your version of macOS. Claude Code needs macOS 13 or later.
What to do: Check your macOS version, then follow Anthropic’s fix for reinstalling the right build.
What it means: A folder in the way of one of Claude Code’s settings paths makes the update check hang.
What to do: Anthropic’s page explains which folder to look for and how to move it.
What it means: Windows’ script policy is stopping the npm version of Claude Code from starting.
What to do: Anthropic’s page explains the safe way to allow it, or you can switch to the native installer, which avoids this.
What it means: npm installed the package but skipped the part that downloads the actual program.
What to do: Anthropic’s page explains how to complete the install, or you can use the native installer instead.
What it means: A leftover folder from an earlier install is blocking npm.
What to do: Anthropic’s page explains which folder to remove before trying again.
What it means: The update was interrupted while replacing the program file.
What to do: Anthropic’s page explains how to restore it from the backup the updater leaves behind.
What it means: Anthropic only offers Claude Code in supported countries.
What to do: Check Anthropic’s list of supported countries.
What it means: Claude Code couldn’t sign you in. Most often the account isn’t on a plan that includes Claude Code (it needs Pro, Max, Team, Enterprise, or a Console account; the free plan doesn’t include it), or the browser sign-in didn’t complete.
What to do: Check your plan, then try signing in again. Anthropic’s page covers the other causes.
What it means: On a Team or Enterprise plan, your role doesn’t include Claude Code.
What to do: Ask your Claude admin for a role that includes Claude Code.
What it means: Claude Code couldn’t reach Anthropic’s servers, usually because of a network, proxy, or firewall issue.
What to do: Try a different network or check with IT. Anthropic’s error reference has the full checklist.
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This page explains errors; it doesn’t give you commands to run. Fixes that involve your terminal should come from Anthropic’s official troubleshooting guide, which is kept up to date. If you’re on a work computer, check with IT before changing system settings. Error list last checked October 9, 2026.
By far the most common. The install worked, but the terminal window you installed from doesn’t know about the new program yet. Closing the window and opening a new one fixes it for most people. If it doesn’t, the install folder isn’t on your PATH, the list of places your terminal looks for programs, and Anthropic’s guide shows how to add it for your system.
Windows has two command windows, PowerShell and Command Prompt, and each needs its own install command. Errors like “irm is not recognized” or “the token && is not a valid statement separator” mean the command and the window don’t match. PowerShell shows “PS” at the start of the line; Command Prompt doesn’t.
Errors mentioning “unexpected token <” or “DOCTYPE html” mean the download address sent back a web page. The usual causes are being in a country where Claude Code isn’t available, or a company network that blocks the download.
If Claude Code installs but won’t sign you in, check your plan first. Claude Code needs Pro, Max, Team, Enterprise, or an Anthropic Console account; the free plan doesn’t include it. On Team and Enterprise plans, your admin may also need to give your role access to Claude Code.
Knowing what the installer does makes most errors easier to understand. When you run Anthropic’s install command, three things happen. First, your computer downloads a small script from Anthropic. Second, that script works out what kind of computer you have and downloads the matching version of Claude Code. Third, it puts the program in a folder inside your user account and sets things up so your terminal can find it.
Errors at the first step are almost always about the network: a firewall, a proxy, a regional block, or a dropped connection. Errors at the second step are about your system: an unsupported version, the wrong type of processor, or not enough memory. Errors at the third step are about permissions and the PATH, which is why “command not found” is so common. And errors after that, when you first run Claude Code, are usually about your account and plan rather than the install itself.
If you installed with a package manager such as Homebrew or WinGet, or with npm, the same three stages apply, but updates work differently: native installs update themselves, while package-manager installs need you to update them. Our Claude download guide compares the methods.
Install problems are frustrating, and it’s tempting to keep trying fixes from forums until something works. Resist that, especially on a work computer. Stop and ask for help if:
On a work device, your IT team is the right first call. Otherwise, Anthropic’s help center has support options, and if you don’t need the terminal version at all, the desktop app runs the same Claude Code agent with nothing to install from the command line.
The lookup covers 28 errors from Anthropic’s troubleshooting guide, grouped by when they happen: during install (download blocked, wrong command, permissions, memory, certificates), on first run (command not found, wrong build for your system, missing shell on Windows), during sign-in (plan, organization access, connection), and during updates (hangs, leftover files, a missing program after an update on Windows). Clear the search box to browse them all.
You may not need Claude Code at all. If you want Claude’s help with documents, research, and everyday work, the Claude desktop app does that with nothing to install from the terminal. Our Claude download guide explains which version you need, and the free Claude Cowork course shows how to use it.
The install usually worked, but your terminal doesn’t know where the new program is yet. Open a new terminal window first. If that doesn’t fix it, the install folder needs to be added to your PATH; Anthropic’s troubleshooting page has the steps for each system.
Fixes often involve running commands on your computer, and the right command depends on your exact setup. Anthropic maintains the official instructions and keeps them current, so we explain what the error means and send you to their fix.
No. Claude Code needs a Pro, Max, Team, or Enterprise plan, or an Anthropic Console account. The free Claude plan doesn’t include it, which is a common cause of sign-in errors.
Try searching for a shorter part of the message. If there’s still no match, check Anthropic’s full troubleshooting page, which covers more cases, or ask in your team’s IT channel if you’re on a work computer or network.
No. The search runs in your browser against a fixed list. Nothing you paste leaves your computer.