I try to connect to an Exchange mail account, but when I try to get messages, i get the “The underlying connection was closed: Could not establish trust relationship for the SSL/TLS secure channel” error.
Looking arround the Internet, I found that I have to use
Function CertificateValidationCallBack( _ ByVal sender As Object, _ ByVal certificate As X509Certificate, _ ByVal chain As X509Chain, _ ByVal sslPolicyErrors As SslPolicyErrors _ ) As Boolean Return True End Function And then ServicePointManager.ServerCertificateValidationCallback = New RemoteCertificateValidationCallback(AddressOf CertificateValidationCallBack) I try the following to connect Dim credential As System.Net.NetworkCredential = New System.Net.NetworkCredential(System.Configuration.ConfigurationManager.AppSettings(“readerusername”), System.Configuration.ConfigurationManager.AppSettings(“readerpassword”), “LAWOFFICE”) eventlog1.WriteEntry(“credentials ok”) Dim client As ExchangeWebServiceClient = New ExchangeWebServiceClient(“https://ip/owa”, credential) eventlog1.WriteEntry(“Successfully connected to Microsoft Exchange server.”)
The problem is that, I cannot use ServicePointManager because in my code I get a build error that “Name ServicePointManager is not declared”
Could you please help me???