(PowerShell) IMAP Download and Verify Signed (S/MIME) Email

Demonstrates how to download and verify digitally signed S/MIME email.

Chilkat .NET Downloads Chilkat .NET Assemblies

Add-Type -Path "C:\chilkat\ChilkatDotNet47-9.5.0-x64\ChilkatDotNet47.dll"

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

$imap = New-Object Chilkat.Imap

# Connect to an IMAP server.
# Use TLS
$imap.Ssl = $true
$imap.Port = 993
$success = $imap.Connect("imap.someMailServer.com")
if ($success -ne $true) {
    $($imap.LastErrorText)
    exit
}

$success = $imap.Login("myLogin","myPassword")
if ($success -ne $true) {
    $($imap.LastErrorText)
    exit
}

# Select an IMAP mailbox
$success = $imap.SelectMailbox("Inbox")
if ($success -ne $true) {
    $($imap.LastErrorText)
    exit
}

# We can choose to fetch UIDs or sequence numbers.
$fetchUids = $true

# Get the message IDs of all the emails in the mailbox
$messageSet = $imap.Search("ALL",$fetchUids)
if ($imap.LastMethodSuccess -ne $true) {
    $($imap.LastErrorText)
    exit
}

# Scan for emails with attachments, and save the attachments
# to a sub-directory.
$i = 0
while ($i -lt $messageSet.Count) {

    $uid = $messageSet.GetId($i)
    $("uid: " + $uid)

    $email = $imap.FetchSingle($uid,$true)

    # The security layers of signed and/or encrypted emails
    # are automatically "unwrapped" when loaded into
    # a Chilkat email object.
    # An application only needs to check to see if an email
    # was received signed or encrypted, and then examine
    # the success/failure.  For example:
    if ($email.ReceivedSigned -eq $true) {

        $("This email was signed.")

        # Check to see if the signatures were verified.
        if ($email.SignaturesValid -eq $true) {
            $("Digital signature(s) verified.")

            $("Signer: " + $email.SignedBy)

            # The certificate used for signing may be obtained
            # by calling email.GetSignedByCert.
            $cert = $email.GetSignedByCert()
            if ($email.LastMethodSuccess -ne $true) {
                $("Failed to get signing certificate object.")
            }
            else {
                $("Signing cert: " + $cert.SubjectCN)

            }

        }
        else {
            $("Digital signature verification failed.")
        }

    }

    $i = $i + 1
}

# Disconnect from the IMAP server.
$success = $imap.Disconnect()