Error map
No authenticationScheme was specified InvalidOperationException: No authenticationScheme was specified, and there was no DefaultChallengeScheme found
.NET · 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)
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…
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…
error: You must be logged in to the server (Unauthorized)
The cluster rejected kubectl’s credentials — expired token, wrong kubeconfig user, or cloud IAM identity not allowed.
denied: requested access to the resource is denied (docker push)
You’re logged in, but not allowed to push to that repository — usually the image isn’t tagged with your own username/organisation.
invalid_token: The access token is invalid (JsonWebTokenError: invalid signature / jwt malformed)
A token was sent but the server couldn’t verify it — bad signature, malformed, revoked, or issued for another audience or environ…
InvalidOperationException: Unable to resolve service for type 'X' while attempting to activate 'Y'
ASP.NET Core’s dependency injection container can’t build Y because one of its constructor dependencies (X) was never registered.
Bearer error="invalid_token": IDX10223: Lifetime validation failed. The token is expired / IDX10501: Signature validation failed
ASP.NET Core’s JwtBearer middleware rejected the token — expired (IDX10223), signature key not found (IDX10501/IDX10503), or wron…
HTTP 401 Unauthorized
The request has no valid authentication credentials — you need to log in or send a valid token.
ReplyError: NOAUTH Authentication required.
The Redis server requires a password (or ACL user) but the client didn’t authenticate.
denied: Your authorization token has expired. Reauthenticate and try again. (Amazon ECR)
Docker’s login to Amazon ECR has expired — ECR tokens last 12 hours, so pushes and pulls fail until you log in again.
UnrecognizedClientException: The security token included in the request is invalid
The access key or session token isn’t recognised — wrong/deleted key, a session token missing for temporary credentials, or a reg…
IDX20803: Unable to obtain configuration from: 'https://login.example.com/.well-known/openid-configuration'
The OpenID Connect / JWT bearer middleware couldn’t download the identity provider’s metadata, so it can’t validate tokens or red…
Two steps away (36)
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.
HTTP 400 Bad Request
The server could not understand the request because its syntax, headers or body are malformed or invalid.
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…
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.
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.
AWS: ExpiredToken — The security token included in the request is expired
Temporary AWS credentials (STS/SSO/assumed role) have expired.
kubectl: The connection to the server localhost:8080 was refused — did you specify the right host or port?
kubectl has no usable kubeconfig, so it falls back to localhost:8080 — or the cluster API server is unreachable.
Error from server (Forbidden): pods is forbidden: User "x" cannot list resource "pods" in API group "" in the namespace
You’re authenticated to the cluster, but RBAC doesn’t give your user or service account that verb on that resource.
Git: ! [rejected] … (fetch first) — error: failed to push some refs
The remote branch has commits you don’t have locally, so Git refuses to overwrite them. Pull (merge or rebase) first, then push.
Azure AD (Entra ID): AADSTS50076 / AADSTS50079 — multi-factor authentication required
A Conditional Access policy requires MFA, but the sign-in flow (often a script, legacy client or ROPC password grant) can’t compl…
error: src refspec main does not match any
You pushed a branch name that doesn’t exist locally — usually no commits yet, or the branch is called master not main.
Git: Permission denied (publickey). fatal: Could not read from remote repository.
SSH authentication to GitHub/GitLab/Bitbucket failed — no key, wrong key, or the key isn’t added to your account.
remote: Repository not found. fatal: repository 'https://github.com/x/y.git/' not found
GitHub/GitLab says the repository doesn’t exist — or you lack access to a private repo.
fatal: Authentication failed for 'https://github.com/x/y.git/'
HTTPS authentication to the Git host failed — wrong or expired credentials, or a password used where a token is required.
System.NullReferenceException: Object reference not set to an instance of an object
Code dereferenced a variable that is `null` — the .NET equivalent of Java’s NullPointerException.
HTTP Error 500.30 - ASP.NET Core app failed to start
IIS/Azure’s ASP.NET Core Module launched your app but it crashed during startup.
JsonException: A possible object cycle was detected
System.Text.Json found a reference loop (e.g. Order → Customer → Orders → …) while serialising, usually from EF Core navigation p…
remote: Support for password authentication was removed on August 13, 2021. Please use a personal access token instead.
GitHub no longer accepts account passwords for Git over HTTPS.
Host key verification failed. fatal: Could not read from remote repository.
SSH doesn’t trust the server’s host key — first connection in a non-interactive environment, or the key changed.
! [remote rejected] … (refusing to allow a Personal Access Token to create or update workflow `.github/workflows/x.yml` without `workflow` scope)
Your token can’t modify GitHub Actions workflow files without the workflow scope.
Kubernetes: ImagePullBackOff / ErrImagePull
The node can’t pull the container image — wrong name/tag, missing registry credentials, or registry unreachable.
HTTP 407 Proxy Authentication Required
A proxy between you and the server requires credentials before it will forward your request.
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…
WRONGTYPE Operation against a key holding the wrong kind of value
A Redis command was used on a key of a different type (e.g. HGET on a string key).
{"message":"Missing Authentication Token"} / No authorization token was found
The request reached a protected endpoint without credentials — or, on AWS API Gateway, it hit a path/method that doesn’t exist.
AADSTS50126: Error validating credentials due to invalid username or password
Microsoft Entra ID (Azure AD) rejected the sign-in because the username or password is wrong — or the flow can’t use passwords fo…
npm ERR! code E401 — Unable to authenticate, need: Basic realm / Incorrect or missing password
The registry rejected your credentials — missing, expired or wrong auth token.
npm ERR! code ENEEDAUTH — need auth This command requires you to be logged in
npm needs credentials (publishing, private packages) but none are configured for that registry.
npm ERR! code EOTP — This operation requires a one-time password from your authenticator
Your npm account has 2FA for writes and no one-time password was supplied.
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…
Azure CLI: Please run 'az login' to setup account / No subscription found
The Azure CLI has no signed-in account (or its token expired), or the account has no subscriptions.
DefaultAzureCredential failed to retrieve a token from the included credentials / ManagedIdentityCredential authentication unavailable
The Azure SDK tried every credential source (env vars, workload identity, managed identity, CLI…) and none worked.
pull access denied for image, repository does not exist or may require 'docker login'
Docker couldn’t pull the image: the name or tag is wrong, the repository is private and you’re not logged in, or it doesn’t exist…
unauthorized: authentication required (docker push / pull)
The registry needs credentials for this operation and the request had none or had expired ones.
error getting credentials - err: exec: "docker-credential-desktop": executable file not found in $PATH
~/.docker/config.json tells Docker to use a credential helper (desktop, osxkeychain, wincred) that isn’t installed or on PATH.
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