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Vb.NET sample for getting the number of Unread messages from an inbox using Impersonation with Exchange Web Services

Although im not a great user of VB any more there does seem to be a bit of a dirth of samples for those people who haven't made the leap to using C#. So here's something that might fill the void for a few people I've put a donwload of this code here the code itself looks like

Imports ewsvbsamp.ews
Imports System.Net
Imports System.Net.Security
Imports System.Security.Cryptography.X509Certificates
Module Module1

Sub Main()
Console.WriteLine(GetUnreadEmailCount("user@domain.com"))
End Sub
Public Function GetUnreadEmailCount(ByVal emailaddress As String) As Integer
Dim UnreadCount As Integer = 0
ServicePointManager.ServerCertificateValidationCallback = New RemoteCertificateValidationCallback(AddressOf ValidateCertificate)
Dim esb As New ExchangeServiceBinding
esb.RequestServerVersionValue = New RequestServerVersion
esb.RequestServerVersionValue.Version = ExchangeVersionType.Exchange2007_SP1
esb.Credentials = New NetworkCredential("user", "password", "domain")
esb.Url = "https://servername/EWS/Exchange.asmx"

Dim csConSid As New ConnectingSIDType
csConSid.PrimarySmtpAddress = emailaddress
Dim exImpersonate As New ExchangeImpersonationType
exImpersonate.ConnectingSID = csConSid
esb.ExchangeImpersonation = exImpersonate

Dim biArray(1) As BaseFolderIdType
Dim dfFolder As New DistinguishedFolderIdType
dfFolder.Id = DistinguishedFolderIdNameType.inbox
biArray(0) = dfFolder
Dim geGetFolder As New GetFolderType
geGetFolder.FolderIds = biArray
geGetFolder.FolderShape = New FolderResponseShapeType
geGetFolder.FolderShape.BaseShape = DefaultShapeNamesType.AllProperties
Dim gfResponse As GetFolderResponseType = esb.GetFolder(geGetFolder)
Dim rmta As ResponseMessageType() = gfResponse.ResponseMessages.Items
Dim rmt As FolderInfoResponseMessageType = DirectCast(rmta(0), FolderInfoResponseMessageType)
If rmt.ResponseClass = ResponseClassType.Success Then
Dim folder As FolderType = DirectCast(rmt.Folders(0), FolderType)
UnreadCount = folder.UnreadCount
End If
Return UnreadCount
End Function

Private Function ValidateCertificate(ByVal sender As Object, ByVal certificate As X509Certificate, ByVal chain As X509Chain, ByVal sslPolicyErrors As SslPolicyErrors) As Boolean
'Return True to force the certificate to be accepted.
Return True
End Function
End Module

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All sample scripts and source code is provided by for illustrative purposes only. All examples are untested in different environments and therefore, I cannot guarantee or imply reliability, serviceability, or function of these programs.

All code contained herein is provided to you "AS IS" without any warranties of any kind. The implied warranties of non-infringement, merchantability and fitness for a particular purpose are expressly disclaimed.