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Mark IMAP Email as Read/Unread (Seen/Unseen)

Demonstrates how to mark emails as read or unread.

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

$success = $false

# This example assumes 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 = $imap.Connect("imap.example.com")
if ($success -eq $false) {
    $($imap.LastErrorText)
    exit
}

# Login
$success = $imap.Login("myLogin","myPassword")
if ($success -eq $false) {
    $($imap.LastErrorText)
    exit
}

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

# Set PeekMode so that downloaded messages are not
# automatically marked as seen.
$imap.PeekMode = $true

# The NumMessages property contains the number of messages 
# in the currently selected mailbox.
$numMsgs = $imap.NumMessages
if ($numMsgs -eq 0) {
    exit
}

$email = New-Object Chilkat.Email

for ($i = 1; $i -le $numMsgs; $i++) {
    # Download each email by sequence number (not UID)
    $success = $imap.FetchEmail($false,$i,$false,$email)
    if ($success -eq $false) {
        $($imap.LastErrorText)
        exit
    }

    # If desired, mark the email as SEEN.  There are two
    # ways to do it:

    # 1) Set the flag directly by using the sequence number
    # Indicate that we are passing a sequence number and
    # not a UID:
    $bIsUid = $false
    # Set the SEEN flag = 1 to mark the email as SEEN,
    # or set it to 0 to mark it as not-seen.
    $success = $imap.SetFlag($i,$bIsUid,"SEEN",1)
    if ($success -eq $false) {
        $($imap.LastErrorText)
        exit
    }

    # 2) Alternatively, we can use the email object.
    # When an email is downloaded from the IMAP server
    # Chilkat will add a "ckx-imap-uid" header to the email.
    # This makes it possible to know the UID associated with
    # the email.  (This is not the sequence number, which may change
    # from session to session, but the UID which does not change.
    # The SetMailFlag method is identical to SetFlag, except
    # it gets the UID from the ckx-imap-uid header.
    # For example:
    $success = $imap.SetMailFlag($email,"SEEN",1)
    if ($success -eq $false) {
        $($imap.LastErrorText)
        exit
    }

}

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