Status Events for C# SDK

The PubNub C# Software Development Kit (SDK) reports status events that describe connection state and error conditions. This page explains each status and when it appears.

Subscribe loop

These status events apply to the latest subscription loop architecture introduced in version 6.20.0 and enabled by default in version 7.0.0.

The PubNub C# SDK provides status events to notify you about the state of the SDK through the PNStatusCategory enum and PNException types.

Subscription-related statuses

Status	Description
PNConnectedCategory	The connection has been established and is ready to receive real-time updates.
PNDisconnectedCategory	The connection has been intentionally terminated.
PNUnexpectedDisconnectCategory	The connection was unexpectedly disconnected.
PNConnectionErrorCategory	Failed to establish the initial connection, with details about the error.
PNSubscriptionChangedCategory	The mix of subscribed channels and channel groups has changed. This event returns two lists: one with all subscribed channels and the second with all subscribed channel groups.

Previous status categories

Status	Description	Deprecated in version	Removed in version
PNReconnectedCategory	SDK was able to reconnect to PubNub. Now handled internally without a specific status. For more information on reconnection, refer to Configuration.	6.20.0	Not removed
PNAcknowledgmentCategory	An API call was successful. This status has additional details based on the type of the successful operation. Now handled with operation-specific success callbacks.	6.20.0	Not removed
PNTimeoutCategory	Used when an API operation didn't receive a response from the server in time. Now represented by specific exceptions.	6.20.0	Not removed
PNRequestMessageCountExceededCategory	Received more messages than specified threshold. No direct equivalent; use operation-specific callbacks.	6.20.0	Not removed
PNNetworkIssuesCategory	Indicated network connectivity problems. Now represented as more specific status categories.	6.20.0	Not removed
PNMalformedResponseCategory	PubNub sent a malformed response. This may happen when you connect to a public WiFi that requires you to log in via your web browser first, there is a proxy somewhere returning an HTML access denied error, or if there was an intermittent server issue. This status category is not actively emitted. Malformed responses now trigger a PNUnexpectedDisconnectCategory status with appropriate error details.	6.20.0	Not removed

SDK connection lifecycle

Intermediate states like connecting and reconnecting are now handled internally without emitting specific statuses. For more general information on statuses and reconnection policies, refer to SDK Connection Lifecycle.

Other statuses

The SDK provides additional statuses for various operations:

Status	Description
PNAccessDeniedCategory	Authorization failed, usually due to invalid keys or token.
PNCancelledCategory	The operation was cancelled before completion.
PNDecryptionErrorCategory	Message decryption failed, likely due to incorrect crypto key.
PNTLSConnectionFailedCategory	Secure connection failed due to TLS/SSL issues.
PNTLSUntrustedCertificateCategory	TLS certificate validation failed.
PNBadRequestCategory	The SDK is missing some required parameters, like message, channel, subscribe key, publish key.
PNNetworkIssuesCategory	The SDK is not able to reach PubNub servers because the machine or device doesn't have Internet connection or the SDK is behind a proxy.
PNTimeoutCategory	Processing has failed because of request timeout.
PNNetworkIssuesCategory	The SDK is not able to reach PubNub servers because the machine or device doesn't have Internet connection or the SDK is behind a proxy.
PNUnknownCategory	The captured error is a minor client-side error or an unknown type at the time of SDK development.
PNBadRequestCategory	The SDK is missing some required parameters, like subscribe key or publish key.
PNTimeoutCategory	Processing has failed because of request timeout.
PNReconnectedCategory	SDK was able to reconnect to PubNub.

Error events

The C# SDK uses PNException to provide detailed error information. Most errors are returned in the exception property of the PNStatus object.

Common error types

Error Code	Description
None	No error occurred.
NameResolutionFailure	DNS resolution failed. Please check network connectivity.
PublishOperationTimeout	A publish operation timed out.
ReceiveFailure	Failed to receive data from the server.
ConnectFailure	Failed to connect to the server. Please verify network reachability.
WebRequestCanceled	Request was cancelled before completion.
NoInternet	No internet connection detected.
UnsubscribedAfterMaxRetries	Unsubscribed after maximum retry attempts were exhausted.
MessageTooLarge	Message exceeded size limits.

Key-related errors

Error Code	Description
InvalidKey	The key provided is invalid.
InvalidSubscribeKey	The subscribe key is invalid or missing.
NoUuidSpecified	No UUID was specified.

Resource errors

Error Code	Description
InvalidChannel	A required channel parameter is invalid or missing.
NotSubscribed	Operation attempted on a channel to which you're not subscribed.
DuplicateChannel	Attempted to subscribe to a channel you're already subscribed to.
EmptyGroupSubscription	Cannot subscribe to an empty channel group.
InvalidTimestamp	The timestamp provided is invalid.