Classes
| Class | Description | |
|---|---|---|
|   |  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    a 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.    |  
|   |  CorruptModelException |    The exception that is thrown when the model is or seems corrupt.    |  
|   |  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.    |  
|   |  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.    |  
|   |  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.    |  
|   |  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.    |  
|   |  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.    |  
|   |  WrongUserException |    The exception thrown when a local model is manipulated under a different username than it was created with.    |