Error map
SMTP Error: Could not authenticate WordPress / PHPMailer: SMTP Error: Could not authenticate / SMTP connect() failed
WordPress · layer 4, Application & API
Centre: this error. First ring: errors it is linked with (10). 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 (10)
Contact Form 7: There was an error trying to send your message. Please try again later.
The form submitted, but wp_mail() failed to send — the server can’t send mail or the mail settings are wrong.
550 5.7.1 Relaying denied / Message rejected as spam / Unauthenticated email not accepted
The receiving (or your outgoing) mail server refused the message — relaying isn’t allowed, the sender isn’t authenticated, or it…
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…
WordPress: Are you sure you want to do this? Please try again. (nonce check failed)
A WordPress security nonce didn’t validate — the page was open too long, cached, or a plugin/theme form is broken.
PHP mail() returns false / emails not delivered
PHP’s mail() function failed or emails never arrive (spam or rejected).
SES MessageRejected: Email address is not verified. The following identities failed the check in region
SES refused to send because the From address/domain isn’t verified — or the account is still in the SES sandbox, where recipients…
WordPress: Another update is currently in progress.
WordPress thinks an update is running because the core_updater.lock option exists — usually left behind by a failed/interrupted u…
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.
550 5.1.1 The email account that you tried to reach does not exist (User unknown)
The recipient mailbox doesn’t exist on the receiving server — a typo in the address, a deleted account, or a wrong domain.
550 5.7.26 This mail has been blocked because the sender is unauthenticated (SPF/DKIM/DMARC)
Gmail/Outlook rejected the message because SPF and DKIM didn’t pass for the sender’s domain (DMARC failure).
Two steps away (21)
Warning: A component is changing an uncontrolled input to be controlled
An input’s `value` started as `undefined` (uncontrolled) and later became a defined value (controlled), or vice versa.
Angular: NG8002: Can't bind to 'ngModel' since it isn't a known property of 'input'
The template uses a property binding that no imported directive provides — for ngModel, FormsModule isn’t imported.
ERR_CACHE_MISS: Confirm Form Resubmission
You pressed Back/Refresh on a page that was the result of a form POST, so the browser asks before sending the form again.
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…
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.
WordPress: Sorry, you are not allowed to access this page.
Your user role lacks the capability for that admin screen — or the database table prefix / user capabilities are out of sync afte…
WordPress: The link you followed has expired
Usually an upload (theme, plugin, media) larger than PHP’s upload/post limits — WordPress receives an empty request and shows thi…
WordPress: Updating failed. The response is not a valid JSON response.
The block editor saved via the REST API but got HTML or an error page back — broken permalinks, a security plugin/WAF, or PHP out…
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.
OAuth Error: redirect_uri_mismatch
The redirect URI in your OAuth request doesn’t exactly match one registered for the client in the provider’s console.
hint: You have divergent branches and need to specify how to reconcile them.
Git 2.27+ asks you to choose merge, rebase or fast-forward-only when local and remote both have new commits.
error: gpg failed to sign the data — fatal: failed to write commit object
Commit signing is enabled but GPG couldn’t sign — no TTY for the passphrase, wrong key, or agent not running.
AccessDeniedException: User: arn:aws:iam::... is not authorized to perform: service:Action on resource: ...
The IAM user or role making the call has no permission for that action on that resource — the message names both.
API Gateway {"message": "Internal server error"} 502 — Malformed Lambda proxy response
The Lambda behind an API Gateway proxy integration returned something that isn’t the required {statusCode, headers, body} shape,…
API Gateway: {"message": "Endpoint request timed out"} (504 after 29 seconds)
The backend (usually Lambda) didn’t respond within API Gateway’s integration timeout (29 seconds by default for REST APIs).
WordPress: Briefly unavailable for scheduled maintenance. Check back in a minute.
An update was interrupted and WordPress left its `.maintenance` file behind, so the site stays in maintenance mode.
WordPress login: Error: Cookies are blocked or not supported by your browser. You must enable cookies to use WordPress.
WordPress’s test cookie wasn’t returned on login — often a siteurl/home or domain mismatch, caching of wp-login.php, or headers a…
WordPress: Missed schedule — scheduled posts not publishing (WP-Cron not running)
WP-Cron didn’t fire at the scheduled time, so scheduled posts and tasks (backups, emails, WooCommerce jobs) are late.
HTTP 404 Not Found
The server can’t find anything at the requested URL.
FastCGI sent in stderr: "Primary script unknown"
Nginx passed a script path to PHP-FPM that PHP-FPM couldn’t find — usually a wrong SCRIPT_FILENAME or root.
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.
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