Error map
DisallowedHost django.core.exceptions.DisallowedHost: Invalid HTTP_HOST header: 'x'. You may need to add 'x' to ALLOWED_HOSTS.
Python · layer 4, Application & API
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)
HTTP 400 Bad Request
The server could not understand the request because its syntax, headers or body are malformed or invalid.
django.core.exceptions.ImproperlyConfigured: settings are not configured / SECRET_KEY must not be empty
Django can’t load its settings — DJANGO_SETTINGS_MODULE unset, a required setting missing, or an environment variable not provide…
Error: secretOrPrivateKey must have a value (jsonwebtoken sign)
jwt.sign() got an empty secret — the environment variable holding the JWT secret isn’t loaded.
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.
Cloudflare Error 1000: DNS points to prohibited IP
A proxied DNS record points at a Cloudflare IP address, creating a loop.
MongoDB: MongoParseError: Invalid scheme, expected connection string to start with "mongodb://" or "mongodb+srv://"
The connection string is missing, malformed, or the environment variable holding it is undefined.
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.
Forbidden (403) CSRF verification failed. Request aborted.
Django rejected a POST because the CSRF token was missing, wrong, or the request origin isn’t trusted.
API Error: Feature not enabled for this account (feature_not_enabled / not available on your plan)
The endpoint or option exists, but your account, plan, region or project hasn’t been granted access to it.
You must specify a region. You can also configure your region by running "aws configure" (NoRegionError)
No region is configured for the CLI/SDK call.
InvalidOperationException: The ConnectionString property has not been initialized
The database connection was opened with an empty connection string — the configuration key wasn’t found.
django.db.utils.OperationalError: no such table: app_model
Django queried a table that hasn’t been created — migrations missing or not applied.
Two steps away (36)
HTTP 401 Unauthorized
The request has no valid authentication credentials — you need to log in or send a valid token.
HTTP 405 Method Not Allowed
The URL exists, but it doesn’t accept the HTTP method you used (e.g. POST to a GET-only route).
HTTP 413 Content Too Large (Request Entity Too Large)
The request body is bigger than the server is willing to accept — usually a file upload over the configured limit.
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.
django.template.exceptions.TemplateDoesNotExist: app/page.html
Django searched all template directories and couldn’t find that template.
ValueError: too many values to unpack (expected 2)
Tuple unpacking got more (or fewer) values than variables on the left.
JWT Expired / Invalid Token
The JSON Web Token sent with the request is expired, malformed or signed with a different key, so the API rejects it (usually wit…
Kubernetes: CreateContainerConfigError — secret / configmap not found
Kubernetes can’t build the container’s configuration — usually a referenced Secret, ConfigMap or key doesn’t exist in that namesp…
warning: in the working copy of 'x', LF will be replaced by CRLF the next time Git touches it
Git’s line-ending conversion (core.autocrlf) will change line endings in your working copy.
Azure AD (Entra ID): AADSTS700016 Application not found in the directory
The client ID in your sign-in request doesn’t exist in the tenant you’re authenticating against.
OAuth 2.0 Error: invalid_grant
The authorization code, refresh token or credentials sent to the token endpoint are invalid, expired, already used or were issued…
OAuth 2.0 Error: invalid_client
The OAuth server couldn’t authenticate your application — wrong client ID/secret, wrong auth method, or the client doesn’t exist…
WordPress: Error Establishing a Database Connection
WordPress can’t connect to its MySQL/MariaDB database with the credentials in wp-config.php, or the database server is down.
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.
fatal: unable to access 'https://github.com/…': Could not resolve host: github.com
DNS lookup for the Git host failed from this machine.
Author identity unknown *** Please tell me who you are.
Git doesn’t know your name and email for commits.
Failed to configure a DataSource: 'url' attribute is not specified and no embedded datasource could be configured.
Spring Boot found JDBC/JPA on the classpath but no database URL.
MySQL ERROR 1046 (3D000): No database selected
A query referenced tables without a database selected (no USE and no db in the connection).
fatal: Not possible to fast-forward, aborting.
pull is configured to fast-forward only, but your branch and the remote have diverged.
MySQL ERROR 1153 (08S01): Got a packet bigger than 'max_allowed_packet' bytes
A single statement or row exceeded max_allowed_packet — big BLOBs, huge INSERTs or large dump lines.
TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received undefined
A Node API got an argument of the wrong type — usually undefined because an env var or config value is missing.
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…
Laravel: 419 Page Expired (CSRF token mismatch)
Laravel rejected a POST because the CSRF token was missing, expired or didn’t match the session.
Python was not found; run without arguments to install from the Microsoft Store
Windows ran the Microsoft Store “App execution alias” instead of a real Python installation.
MySQL ERROR 1049 (42000): Unknown database 'x'
The database named in the connection doesn’t exist on that server.
npm update check failed — Try running with sudo or get access to the local update config store
npm’s update notifier couldn’t write its config — usually root-owned files in ~/.config from a past sudo npm.
Warning: file_exists(): open_basedir restriction in effect. File(/x) is not within the allowed path(s)
PHP is configured to access only certain directories, and the script tried to touch a file outside them.
AWS: Unable to locate credentials / Could not load credentials from any providers
The AWS CLI/SDK found no credentials in any place it looks — env vars, profile files, SSO cache or an instance/task role.
Laravel: No application encryption key has been specified.
Laravel’s APP_KEY is missing, so it can’t encrypt sessions and cookies.
PHP mail() returns false / emails not delivered
PHP’s mail() function failed or emails never arrive (spam or rejected).
PHP upload error 1: The uploaded file exceeds the upload_max_filesize directive in php.ini
The uploaded file is bigger than PHP’s upload_max_filesize, so PHP discarded it.
Warning: Unknown: Input variables exceeded 1000. To increase the limit change max_input_vars in php.ini.
The form submitted more fields than PHP’s max_input_vars allows; extra fields were silently dropped.
FATAL: database "x" does not exist
The connection names a database that isn’t on that server.
MySQL ERROR 1146 (42S02): Table 'db.table' doesn't exist
The query references a table that MySQL can’t find in that database.
PostgreSQL: ERROR: relation "x" does not exist
The table/view isn’t found — missing migration, wrong schema, or a case-sensitive quoted name.
MySQL ERROR 1022 (23000): Can't write; duplicate key in table
An ALTER/CREATE produced a duplicate key or constraint name — often a foreign key name that already exists in the database.
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