Error map
Rogue DHCP server hands out wrong gateway/DNS Networking: Clients receive the wrong default gateway or DNS server — a rogue DHCP server (often a home router) answers first
Networking · layer 2, Network
Centre: this error. First ring: errors it is linked with (12). Outer ring: what those are linked with. Colours show the layer of a request each error belongs to. Click any dot to re-centre the map on it; hover to follow its connections. The centre dot opens the error page.
Directly related (12)
Cloudflare Error 1005: Access denied — The owner of this website has banned the autonomous system number (ASN) your IP address is in
The site owner blocked your network provider (ASN) — common for VPNs, cloud/data-center IPs and some mobile carriers.
Cloudflare Error 1015: You are being rate limited
The site’s Cloudflare rate-limiting rule blocked you for sending too many requests in a short time.
Cloudflare-branded 502 Bad Gateway / 504 Gateway Timeout ("cloudflare" footer)
A plain-looking 502/504 page with “cloudflare” at the bottom comes from Cloudflare’s network itself (or an origin response it cou…
AADSTS50053: Your account is locked (Smart Lockout) / sign-in blocked due to suspicious activity
Too many failed sign-ins (or sign-ins from a malicious IP) triggered Entra Smart Lockout.
Cloudflare Turnstile error 110200 / 300030 / 600010 (widget fails to load or verify)
The Turnstile widget couldn’t run or validate — wrong sitekey/domain, blocked scripts, or a client/network issue.
Cloudflare Error 1006 / 1007 / 1008: Access denied — Your IP address has been banned
The site owner (or a Cloudflare security setting) blocked your IP address.
Cloudflare Error 1009: Access denied — The owner of this website has banned the country or region your IP address is in
The site blocks visitors from your country/region.
Cloudflare "Just a moment..." / "Checking your browser" challenge loop (Verify you are human never finishes)
The Cloudflare challenge keeps reloading — the browser can’t pass it because cookies/JavaScript are blocked, the clock is wrong,…
API/app requests get 403 with cf-mitigated: challenge (Bot Fight Mode / challenge on non-browser clients)
Cloudflare is answering API calls, webhooks or mobile-app requests with a challenge page (HTML 403) because bot protection treats…
Cloudflare Error 1012: Access denied
The site owner blocked access with a rule that matched your request (often due to malicious activity detected from your IP).
Windows protected your PC — Microsoft Defender SmartScreen prevented an unrecognized app from starting
SmartScreen blocked an app that’s unsigned or new/rare (no download reputation yet).
Cloudflare Error 1010: The owner of this website has banned your access based on your browser's signature
Cloudflare’s bot detection blocked the request because its browser fingerprint looks automated.
Two steps away (33)
Webhook signature verification failed (Stripe, Razorpay, GitHub…)
Your endpoint computed a different HMAC signature than the one the provider sent, so the webhook is rejected.
Cloudflare Error 1020: Access Denied
A Cloudflare firewall/WAF custom rule blocked the request — the visitor’s IP, country, user agent or request pattern matched a bl…
driver failed programming external connectivity on endpoint: iptables: No chain/target/match by that name
Docker’s iptables rules were wiped (firewalld/ufw reload, iptables flush) while Docker was running, so it can’t publish ports.
AWS: ThrottlingException / Rate exceeded
You exceeded the request rate for an AWS API; retry with exponential backoff.
HTTP 429 Too Many Requests
You’ve hit a rate limit — too many requests in a given time window. Slow down and retry later.
API Error: Too many concurrent requests (concurrency limit reached)
You have more requests in flight at once than the API allows for your key — even if your requests-per-minute rate is fine.
HTTP 502 Bad Gateway
A proxy or gateway (Nginx, load balancer, CDN) got an invalid response — or no response — from the upstream server behind it.
HTTP 504 Gateway Timeout
A proxy or gateway waited too long for the upstream server to respond and gave up.
Cloudflare Error 520: Web Server Returned an Unknown Error
Cloudflare connected to your origin, but the origin returned an empty, unknown or invalid response.
Error creating: pods is forbidden: violates PodSecurity "restricted:latest": allowPrivilegeEscalation != false ...
The namespace enforces a Pod Security Standard (baseline/restricted) and the pod spec breaks one of its rules.
WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! (ssh host key changed)
The server’s SSH host key differs from the one saved in ~/.ssh/known_hosts — usually because the server was rebuilt or the IP was…
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY
apt can’t verify a repository’s signature because the repo’s signing key isn’t installed (or has expired/rotated).
API Error: Invalid API Key / Incorrect API key provided
The API didn’t recognise the key sent with the request — it’s wrong, revoked, from another environment, or sent in the wrong plac…
Cloudflare Error 1011: Access denied (Hotlinking denied)
An image or file is being loaded from another site, and Cloudflare Hotlink Protection blocked it.
java.lang.SecurityException: Permission Denial ... requires android.permission.X
The app called an API that needs a permission it hasn’t declared or the user hasn’t granted at runtime.
ssh: connect to host x port 22: Connection timed out
SSH packets get no reply — a firewall/security group drops them, the server is off, or the IP is wrong.
connect: No route to host (EHOSTUNREACH)
The destination host isn’t reachable — it’s down, on another subnet without routing, or a firewall rejects with “host unreachable…
Azure SQL: Cannot open server 'x' requested by the login. Client with IP address 'y' is not allowed to access the server (Error 40615)
The Azure SQL server firewall doesn’t allow your client’s IP address.
HTTP 451 Unavailable For Legal Reasons
The content is blocked for legal reasons — a court order, government censorship, sanctions, or GDPR geo-blocking.
ASP.NET Core: The antiforgery token could not be decrypted / The required antiforgery cookie is not present (400 Bad Request)
Form POST failed antiforgery validation — the token is missing, the cookie is missing, or Data Protection keys changed so old tok…
WordPress: 403 Forbidden on wp-admin, wp-login.php or admin-ajax.php
The server or a security layer refused access to WordPress admin URLs — file permissions, a security plugin/WAF rule, ModSecurity…
HTTP 418 I'm a teapot
An April Fools’ status from RFC 2324 — some sites and WAFs return it on purpose to tell bots or scrapers to go away.
Nginx 444 No Response (connection closed without response)
An Nginx-specific code: the server deliberately closed the connection without sending anything — a rule is dropping the request.
JWT error: invalid algorithm / The specified alg value is not allowed / jwt signature is required
The token’s alg header doesn’t match the algorithms the verifier allows — e.g. RS256 token verified as HS256, or an unsigned (alg…
HTTP 403 Forbidden
The server understood the request but refuses to authorize it — you (or the server process) are not allowed to access this resour…
SyntaxError: Unexpected token < in JSON at position 0
`JSON.parse()` / `response.json()` received something that isn’t JSON — very often an HTML error page.
ForbiddenError: invalid csrf token (EBADCSRFTOKEN)
The request’s CSRF token is missing or doesn’t match the token tied to the user’s session/cookie.
macOS: “App” is damaged and can’t be opened. You should move it to the Trash.
Gatekeeper blocked an app that isn’t properly signed/notarized or was modified after download (quarantine attribute).
Let's Encrypt: Fetching http://example.com/.well-known/acme-challenge/token: Timeout during connect (likely firewall problem)
The ACME validation server could not reach your server on port 80 within the timeout.
Networking: ping — Request timed out / 100% packet loss (host drops or filters ICMP)
No echo reply arrived in time: the host is down, unreachable, or simply ignores ping.
Xcode: No signing certificate "iOS Development" found
Xcode can’t find a valid code-signing certificate + private key for the selected team in your keychain.
0x800704EC: This program is blocked by group policy (Windows Defender)
Windows Security/Defender can’t start because another antivirus or a group policy has turned it off.
File cannot be loaded because running scripts is disabled on this system (PowerShell execution policy)
PowerShell’s execution policy blocks .ps1 scripts — including npm/yarn/pnpm shims like npm.ps1.
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