Powershell send s/mime encrypted mail with attachment

Question

Hi Guys!
I've a tricky challenge.
I try to send powershell generated emails with an attachment and - on top - s/mime encrypted.
My current state of work:
send encrypted emails (without attachment) - success
send unencrypted emails (with attachment) - success
send encrypted emaisl (with attachment) - failed
Do anyone have a solution of this?
Thanks in advance!!!
cls
$RecipientCN = $null
$RootDSE = $null
$Certificate = $null
$UserCertificate = $null
$ExcelFile = "C:\Temp\123.xlsx"
$RecipientCN='<cn>'
$SearchForestForPerson = New-Object DirectoryServices.DirectorySearcher([ADSI]"LDAP://DC=domain,DC=com")
$SearchForestForPerson.SearchScope = "subtree"
$SearchForestForPerson.PropertiesToLoad.Add("mail") | Out-Null
$SearchForestForPerson.PropertiesToLoad.Add("usercertificate") | Out-Null
$SearchForestForPerson.Filter = ("(&(objectClass=person)(CN=$RecipientCN))")
$Recipient = $SearchForestForPerson.FindOne()
$ChosenCertificate = $null
$Now = Get-Date
If ($Recipient.Properties.usercertificate -ne $null) {
ForEach ($UserCertificate in $Recipient.Properties.usercertificate) {
$ValidForSecureEmail = $false
$Certificate = [System.Security.Cryptography.X509Certificates.X509Certificate2]$UserCertificate
$Extensions = $Certificate.Extensions
ForEach ($Extension in $Extensions) {
If ($Extension.EnhancedKeyUsages -ne $null) {
ForEach ($EnhancedKeyUsage in $Extension.EnhancedKeyUsages) {
If ($EnhancedKeyUsage.FriendlyName -ine "Secure Email") {
$ValidForSecureEmail = $true
break
If ($ValidForSecureEmail) {
break
If ($ValidForSecureEmail) {
If ($Now -gt $Certificate.NotBefore.AddMinutes(-5) -and $Now -lt $Certificate.NotAfter.AddMinutes(5)) {
$ChosenCertificate = $Certificate
If ($ChosenCertificate -ne $null) {
break
Add-Type -assemblyName "System.Security"
$MailClient = New-Object System.Net.Mail.SmtpClient "<Smtp-Server>"
$Message = New-Object System.Net.Mail.MailMessage
$Message.To.Add($Recipient.properties.mail.item(0))
$Message.From = "<sender address>"
$Message.Subject = "Unencrypted subject of the message"
$Body = "This is the mail body"
$MIMEMessage = New-Object system.Text.StringBuilder
$MIMEMessage.AppendLine('Content-Type: text/plain; charset="UTF-8"') | Out-Null
$MIMEMessage.AppendLine('Content-Transfer-Encoding: 7bit') | Out-Null
$MIMEMessage.AppendLine() | Out-Null
$MIMEMessage.AppendLine($Body) | Out-Null
$MIMEMessage.Append($ExcelFile) | Out-Null
[Byte[]] $BodyBytes = [System.Text.Encoding]::ASCII.GetBytes($MIMEMessage.ToString())
$ContentInfo = New-Object System.Security.Cryptography.Pkcs.ContentInfo (,$BodyBytes)
$CMSRecipient = New-Object System.Security.Cryptography.Pkcs.CmsRecipient $ChosenCertificate
$EnvelopedCMS = New-Object System.Security.Cryptography.Pkcs.EnvelopedCms $ContentInfo
$EnvelopedCMS.Encrypt($CMSRecipient)
[Byte[]] $EncryptedBytes = $EnvelopedCMS.Encode()
$MemoryStream = New-Object System.IO.MemoryStream @(,$EncryptedBytes)
$AlternateView = New-Object System.Net.Mail.AlternateView($MemoryStream, "application/pkcs7-mime; smime-type=enveloped-data;name=smime.p7m")
$Message.AlternateViews.Add($AlternateView)
$MailClient.Send($Message)

Answer 1

You posted to the wrong forum (MDM).  You can try this one:
http://social.technet.microsoft.com/Forums/scriptcenter/en-US/home
Jeff Sanders (MSFT)
@jsandersrocks - Windows Store Developer Solutions
@WSDevSol
Getting Started With Windows Azure Mobile Services development?
Click here
Getting Started With Windows Phone or Store app development?
Click here
My Team Blog: Windows Store & Phone Developer Solutions
My Blog: Http Client Protocol Issues (and other fun stuff I support)