Classes

	Class	Description
	AccessDeniedException
	ApplicationException	The exception that is thrown when a non-fatal application error occurs.
	ArgumentException	The exception that is thrown when one of the arguments provided to a method is not valid.
	ArgumentNullException	The exception that is thrown when nullNothingnullptra null reference (Nothing in Visual Basic) is passed to a method that does not accept it as a valid argument.
	ArgumentOutOfRangeException	The exception that is thrown when the value of an argument is outside the allowable range of values as defined by the invoked method.
	ArgumentsInconsistentException	The exception that is thrown when each individual argument is OK, but a joint constraint is violated.
	AutoJoinFailedException	The exception that is thrown when an autojoin operation failed.
	BackgroundTaskCancelledException	The exception thrown when Revit cancels a background operation. Third-party developers are not expected to catch and handle this exception. Instead, if allowed to propagate back to Revit code, it will be handled by Revit.
	CannotOpenBothCentralAndLocalException	The exception thrown when both a central model and also a local file for the same central model are opened in the same session.
	CentralFileCommunicationException	The exception thrown when there is a network communication error involving a file-based central model.
	CentralModelAccessDeniedException	The exceptions thrown when a central model can be reached but access is denied due to a lack of access privileges.
	CentralModelAlreadyExistsException	Exception is thrown when the central model already exists at the specified location.
	CentralModelContentionException	The exception thrown when a central model is busy (locked) and the operation is canceled.
	CentralModelException	The base class for exceptions that are common to both file-based and server-based central models or specific to just file-based central models.
	CentralModelVersionArchivedException	Exception is thrown when last central version merged into the local model has been archived in the central model. Reload Latest or Synchronized with Central needs to be conducted before the current failed operation is retried.
	CheckoutElementsRequestTooLargeException	Exception is thrown when too many elements are requested for checkout
	CorruptModelException	The exception that is thrown when the model is or seems corrupt.
	DefaultValueException	The exception thrown when Revit cannot initialize a default value for a family parameter.
	DirectoryNotEmptyException	The exception that is thrown when a method received a directory as an argument and requires that the directory be empty but the directory is not empty.
	DirectoryNotFoundException	The exception that is thrown when the specified directory could not be found.
	DisabledDisciplineException	The exception that is thrown when the function cannot execute because a discipline is disabled. The exception specifies which discipline(s) would let the operation succeed.
	ExternalApplicationException	The exception that is thrown when an issue in the Add-Ins resulted in an unexpected error.
	FamilyContextException	The exception that is thrown when an operation is invalid in the current family document, because of the type of family.
	FileAccessException	The exception that is thrown when the specified file could not be accessed, e.g. read-only, locked by the OS etc.
	FileArgumentAlreadyExistsException	The exception that is thrown when the specified file exists.
	FileArgumentNotFoundException	The exception that is thrown when a method received a filename as an argument and requires it to exist as a precondition.
	FileNotFoundException	The exception that is thrown when the specified file could not be found.
	ForbiddenForDynamicUpdateException	The exception that is thrown when making or attempting to make changes that are forbidden during dynamic updates to the model.
	FunctionId	The information of a function throwing an exception.
	InapplicableDataException	The exception that is thrown when attempting to access a piece of data that is structurally not part of an object at the moment.
	InsufficientResourcesException	The exception that is thrown when the OS runs out of resources, e.g. memory, disk space, or USER or GDI objects.
	InternalException	The exception that is thrown when an issue in the Revit code resulted in an unexpected error.
	InvalidDataStreamException	The exception that is thrown when the reading or saving operation failed due to parsing error.
	InvalidObjectException	The exception that is thrown when referencing an object that is no longer valid.
	InvalidOperationException	The exception that is thrown when a method call is invalid for the object's current state.
	InvalidPathArgumentException	The exception that is thrown when a method received a pathname as an argument, but the pathname is illegal: too long, invalid characters, etc.
	IOException	The exception that is thrown when an I/O error occurs.
	ModificationForbiddenException	The exception that is thrown by the undo transaction framework when a modification operation is not allowed.
	ModificationOutsideTransactionException	The exception that is thrown by the undo transaction framework when the modification operation to the model is outside of a transaction.
	NetworkCommunicationException
	NotTransmittedModelException	The exception thrown when OpenOptions were provided to deal with a transmitted model, but the model is not transmitted.
	ObjectAccessException	The exception that is thrown when an operation is denied, e.g. an attempt was made to set a read-only property.
	OperationCanceledException	The exception that is thrown when an operation is unexpectedly cancelled.
	OptionalFunctionalityNotAvailableException	The exception that is thrown when the optional functionality is not available in the installed Revit
	OutdatedDirectlyOpenedCentralException	The exception thrown when a central model is opened directly and its copy in the session is outdated. If the operation is supported for local files, first resave as local, and try again.
	RegenerationFailedException	The exception that is thrown when a regeneration operation failed.
	ResourceNotFoundException
	RevitServerCollaborationNotAvailableException	The exception that is thrown when Collaboration fails because of an external resource (e.g., Amazon S3) failure.
	RevitServerCommunicationException	The exception that is thrown when there is any network communication error happening.
	RevitServerException	The exception that is base class for all exceptions originating from the Revit server.
	RevitServerInternalException	The exception that is thrown when there is any server internal error happening.
	RevitServerModelAlreadyExistsException	The exception that is thrown when there is a model with the same name already exist.
	RevitServerModelNameBreaksConventionException	The exception that is thrown when the model is breaking the project naming convention.
	RevitServerUnauthenticatedUserException	The exception that is thrown when an unauthenticated user attempts to initiate a call to RevitServer.
	RevitServerUnauthorizedException	The exception that is thrown when a call to the server is unauthorized.
	SchemaException	The exception thrown when Revit cannot interpret a data structure described by a schema.
	ServerInternalException
	TransientElementCreationException	The exception that is thrown when TransientElementCreationScope is used incorrectly.
	TransmittedModelException	The exception thrown when model was transmitted (sent by eTransmit) and insufficient OpenOptions were provided to handle its transmitted flag.
	UnauthenticatedException
	WrongUserException	The exception thrown when a local model is manipulated under a different username than it was created with.