DotRAS.dll not working on Windows 10 Update 1803 - vb.net

Question

I have a small VB.NET program, which creates a VPN connection.
This is working until (and including) Windows 10 Update 1709.
But since the Update 1803 I always get an exception:
DotRas.RasException: An incorrect structure size was detected.
at DotRas.Internal.ThrowHelper.ThrowRasException(Int32 errorCode)
at DotRas.Internal.RasHelper.GetEntryProperties(RasPhoneBook phoneBook, String entryName)
at DotRas.RasEntryCollection.Load()
at DotRas.RasPhoneBook.Open(String phoneBookPath)
Following my working Code Sub (until 1709)
Private Sub CreateVPN(VpnName As String, Destination As String, bAllUsers As Boolean)
Dim PresharedKey As String = "XXXXXXXXXXX"
Try
Dim PhoneBook As New RasPhoneBook
Dim sUsedPhoneBook As String = sPhoneBook
If bAllUsers Then sUsedPhoneBook = sAllUserPhoneBook
PhoneBook.Open(sUsedPhoneBook)
'First remove existing VPN with same name, if exist!
Try
PhoneBook.Entries.Remove(VpnName)
Catch ex As Exception
End Try
Dim VpnEntry As RasEntry = RasEntry.CreateVpnEntry(VpnName, Destination, DotRas.RasVpnStrategy.L2tpOnly, DotRas.RasDevice.Create(VpnName, DotRas.RasDeviceType.Vpn))
VpnEntry.Options.UsePreSharedKey = True
VpnEntry.Options.IPHeaderCompression = True
VpnEntry.Options.SoftwareCompression = True
VpnEntry.Options.NetworkLogOn = True
VpnEntry.NetworkProtocols.IPv6 = False
VpnEntry.Options.RequireEap = False
VpnEntry.Options.RequirePap = True
VpnEntry.Options.RequireChap = True
VpnEntry.Options.RequireMSChap2 = True
VpnEntry.Options.RequireEncryptedPassword = False
VpnEntry.Options.UseLogOnCredentials = False
VpnEntry.Options.CacheCredentials = False
VpnEntry.DnsSuffix = "YYYYYYY.local"
VpnEntry.Options.UseDnsSuffixForRegistration = True
' *********** THE FOLLOWING LINE WILL CRASH ON WINDOWS 10 1803 **********
PhoneBook.Entries.Add(VpnEntry)
VpnEntry.UpdateCredentials(RasPreSharedKey.Client, PresharedKey)
If txt_Username.Text <> "" AndAlso txt_Password.Text <> "" Then
VpnEntry.UpdateCredentials(New Net.NetworkCredential(txt_Username.Text, txt_Password.Text), False)
VpnEntry.Options.CacheCredentials = True
VpnEntry.Update()
End If
PhoneBook.Dispose()
txt_Status.Text = VpnName & " successful added."
txt_Status.ForeColor = Color.DarkGreen
Catch ex As Exception
Console.WriteLine("Error while adding " & VpnName & "." & Environment.NewLine & ex.ToString)
Finally
End Try
End Sub
Can somebody help me?
I didn't found an updated DotRAS.dll.
Best would be a working example without external DLL.
Thank you in advance.