The following constants are used to describe the various fax results (disposition) and states of transmission.

/// <summary>
/// FaxResult values.
/// </summary>
public enum EtherFaxResult
{
    Success = 0,
    Error,
    InProgress,
    LineBusy,
    LineDead,
    LineFailure,
    NoDialTone,
    NoAnswer,
    InvalidOrMissingNumber,
    InvalidOrMissingFile,
    InvalidChannel,
    UnexpectedDisconnect,
    NoChannelsAvailable,
    ChannelUnavailable,
    NothingToCancel,
    DeviceTimeout,
    DeviceBusy,
    NotFaxMachine,
    IncompatibleFaxMachine,
    FileError,
    FileNotFound,
    FileUnsupported,
    CallCollision,
    Cancelled,
    CallBlocked,
    DestinationBlackListed,
    RemoteDisconnect,
    NegotiationError,
    TrainingError,

    Unauthorized = 100,
    InvalidParameter,
    NotImplemented,
    ItemNotFound,
    EncryptionDisabled,
    EncryptionRequired,
    DecryptFailure,
    DocumentRejected,
    DocumentNotSupported,
    DocumentTooLarge
}