public bool IsValid { get; }

Public ReadOnly Property IsValid As Boolean
	Get

Property Value

This property exists for compatibility with not fully IMAP4-compliant servers. Due to complexity of IMAP4 responses, some implementation still fail to produce syntactically correct IMAP4 responses in some cases.

The developer can use this property (or subscribe to ErrorOccurred event, see code sample in Envelope topic) to determine if all the data is correct.

Note

This property (if true) does not indicate all properties of Envelope object return actual values. It only relates to the properties for which the data was requested from the server. For instance, if DownloadEnvelopes(String, Boolean, EnvelopeParts, Int32, String, String) method was called with parts parameter set to Uid, only Uid (and MessageNumber, which is always available) properties will be set and IsValid will still return true. However, if UID value could not be parsed in the last case, IsValid would return false.

Reference