NetworkCredential CryptographicException

[Marcus Michaels]

Hi all,

I am using some old code from a 2.0 project in 4.0, trying to communicate
with a SMTP-Server. The code works fine in 2.0.

In 4.0 I receive a CryptographicException (InvalidHandle) when I am trying
to assign the password to the NetworkCredentials. I tried all constructors,
assigning the password to the property directly, but no change.

Underneath please find part of the class and the stack trace.

Imports System.IO
Imports System.Net
Imports System.Net.Mail
Imports System.Net.Mime
Imports HtmlAgilityPack
Imports System.Security

Public Class MailHelper

Property objMail As New MailMessage
Property objSender As MailAddress
Property objTo As MailAddress
Property objCC As MailAddress
Property objBCC As MailAddress
Property objSmtpClient As SmtpClient
Property objSmtpCredentials As NetworkCredential

Property strMapPath As String

Public Sub New(ByVal strServerMapPath As String)

objSender = New MailAddress(GetAppSetting("MessageFromEmail"),
GetAppSetting("MessageFromName"))

objSmtpClient = New SmtpClient(GetAppSetting("SmtpServer"))
objSmtpClient.UseDefaultCredentials = False

Try
Dim x As NetworkCredential = New
System.Net.NetworkCredential("a","b")

objSmtpClient.Credentials = x

Catch ex As Exception

End Try

objMail.From = objSender

strMapPath = strServerMapPath

End Sub

End Class


STACK TRACE:

bei System.Security.SecureString.ProtectMemory()
bei System.Security.SecureString.InitializeSecureString(Char* value,
Int32 length)
bei System.Security.SecureString..ctor(Char* value, Int32 length)
bei
System.Net.UnsafeNclNativeMethods.SecureStringHelper.CreateSecureString(String plainString)
bei System.Net.NetworkCredential..ctor(String userName, String password)