Error map
webhook delivery failed Webhook delivery failed (endpoint returned non-2xx / timed out)
API · layer 4, Application & API
Centre: this error. First ring: errors it is linked with (9). 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 (9)
CORS Error: No 'Access-Control-Allow-Origin' header is present
The browser blocked a cross-origin request because the server’s response didn’t include the CORS headers allowing your site’s ori…
Error: socket hang up / read ECONNRESET
The other side closed the TCP connection abruptly while your client was still using it.
HTTP 504 Gateway Timeout
A proxy or gateway waited too long for the upstream server to respond and gave up.
Internal error occurred: failed calling webhook "x": ... connection refused / context deadline exceeded
The API server couldn’t reach an admission webhook’s service, so it rejected the request (failurePolicy: Fail).
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.
WooCommerce: There was an error processing your order. Please check for any charges in your payment method / Error processing checkout. Please try again.
Checkout failed server-side — payment gateway error, nonce/session issue from caching, or a PHP error from a plugin hook.
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 301 Moved Permanently
The resource has a new permanent URL; clients and search engines should use the address in the Location header from now on.
API Error: Job / operation not found or expired (async task ID unknown)
The status URL or job ID for an asynchronous operation (export, import, render, batch) doesn’t exist any more, or never existed.
Two steps away (27)
AWS S3: AccessDenied (403) when calling GetObject / PutObject
An IAM policy, bucket policy, ACL/ownership setting, Block Public Access or KMS key policy denied the S3 request.
HTTP 401 Unauthorized
The request has no valid authentication credentials — you need to log in or send a valid token.
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…
Error: connect ECONNREFUSED 127.0.0.1:5432
Nothing is listening at that host:port — the target service is down or you’re connecting to the wrong address.
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.
Too many open files (EMFILE)
The process hit its file-descriptor limit — sockets, files and pipes all count.
HTTP 408 Request Timeout
The server closed the connection because the client took too long to send the complete request.
HTTP 500 Internal Server Error
The server hit an unexpected condition — usually an unhandled exception or misconfiguration in the application.
HTTP 503 Service Unavailable
The server is temporarily unable to handle the request — overloaded, in maintenance, or has no healthy backends.
Kubernetes: CrashLoopBackOff
The container starts, crashes (or exits), and Kubernetes keeps restarting it with increasing back-off delays.
Namespace stuck in Terminating
A deleted namespace never disappears because some resource inside it, or the namespace’s own finalizer, can’t be cleaned up.
Error from server (BadRequest): container "x" in pod "y" is waiting to start: ContainerCreating
kubectl logs has nothing to show yet — the container hasn’t started (still creating, pulling, or blocked).
HTTP 400 Bad Request
The server could not understand the request because its syntax, headers or body are malformed or invalid.
AWS: SignatureDoesNotMatch / InvalidClientTokenId — the request signature we calculated does not match
AWS rejected the request signature — wrong secret key, wrong region, clock skew, or a presigned URL used differently from how it…
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.
API Error: a similar object exists in test mode, but a live mode key was used
You’re using an ID, key or URL from one environment (test/sandbox) with credentials from another (live/production), or vice versa.
WordPress: 404 Not Found on every page except the homepage (permalinks / .htaccess / Nginx rules)
Pretty permalinks aren’t being routed to index.php — .htaccess is missing/ignored (Apache) or Nginx lacks try_files.
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…
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.
HTTP 409 Conflict
The request conflicts with the current state of the resource — e.g. a duplicate or an edit based on an outdated version.
HTTP 404 Not Found
The server can’t find anything at the requested URL.
HTTP 410 Gone
The resource used to exist but was intentionally and permanently removed, with no forwarding address.
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: getaddrinfo ENOTFOUND host / Name or service not known
DNS lookup for the hostname failed — the name is wrong, doesn’t exist, or this machine can’t resolve it.
API Error: No such object / resource_missing (resource not found by ID)
The endpoint exists, but the ID you passed — in the URL or as a reference in the body — doesn’t match any record the caller can s…
API Error: Invalid pagination cursor (invalid_cursor / cursor expired)
The page token or cursor you passed is malformed, expired, or was generated for a different query.
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