Powershell script on Exchange server returns 800+ records out of 62000. Why?

Question

Hi,
I've used script below to extract all attachments from mailbox (needed to perform only once). It's a mailbox where reports was sent, so it contains only messages with specific name and attachment.
And it returns only 800+ records out of 60+ thousands. Any advice how to modify it? I've tried to change ItemView from 1000 to 63000, nothing changed.

# Name of the mailbox to pull attachments from
$MailboxName = '******@domain.com'

# Location to move attachments
$downloadDirectory = 'E:\ToExport'

# Path to the Web Services dll
$dllpath = "E:\Exchange\V15\Bin\Microsoft.Exchange.WebServices.dll"
[VOID][Reflection.Assembly]::LoadFile($dllpath)

# Create the new web services object
$service = New-Object Microsoft.Exchange.WebServices.Data.ExchangeService([Microsoft.Exchange.WebServices.Data.ExchangeVersion]::Exchange2019)

# Create the LDAP security string in order to log into the mailbox
$windowsIdentity = [System.Security.Principal.WindowsIdentity]::GetCurrent()
$sidbind = "LDAP://<SID=" + $windowsIdentity.user.Value.ToString() + ">"
$aceuser = [ADSI]$sidbind

# Auto discover the URL used to pull the attachments
$service.AutodiscoverUrl($aceuser.mail.ToString())

# Get the folder id of the Inbox
$folderid = new-object  Microsoft.Exchange.WebServices.Data.FolderId([Microsoft.Exchange.WebServices.Data.WellKnownFolderName]::Inbox,$MailboxName)
$InboxFolder = [Microsoft.Exchange.WebServices.Data.Folder]::Bind($service,$folderid)

# Find mail in the Inbox with attachments
$Sfha = new-object Microsoft.Exchange.WebServices.Data.SearchFilter+IsEqualTo([Microsoft.Exchange.WebServices.Data.EmailMessageSchema]::HasAttachments, $true)
$sfCollection = new-object Microsoft.Exchange.WebServices.Data.SearchFilter+SearchFilterCollection([Microsoft.Exchange.WebServices.Data.LogicalOperator]::And);
$sfCollection.add($Sfha)

# Grab all the mail that meets the prerequisites
$view = new-object Microsoft.Exchange.WebServices.Data.ItemView(63000)
$frFolderResult = $InboxFolder.FindItems($sfCollection,$view)

# Loop through the emails
foreach ($miMailItems in $frFolderResult.Items){

    # Load the message
    $miMailItems.Load()

    # Loop through the attachments
    foreach($attach in $miMailItems.Attachments){

        # Load the attachment
        $attach.Load()

        # Save the attachment to the predefined location
        $fiFile = new-object System.IO.FileStream(($downloadDirectory + “\” + $attach.Name.ToString()), [System.IO.FileMode]::Create)       
                $fiFile.Write($attach.Content, 0, $attach.Content.Length)
        $fiFile.Close()
    }
 }

Answer 1

This is just the section of your code that I think needs modification. I've marked what I've added with "#ADDED" at the end of each line. It follows the code example in the link I posted earlier. I have not tested this:

# Grab all the mail that meets the prerequisites
$view = New-Object Microsoft.Exchange.WebServices.Data.ItemView(63000)

$more = $true   # ADDED
Do {    # ADDED
    $frFolderResult = $InboxFolder.FindItems($sfCollection, $view)

    # Loop through the emails
    foreach ($miMailItems in $frFolderResult.Items) {

        # Load the message
        $miMailItems.Load()

        # Loop through the attachments
        foreach ($attach in $miMailItems.Attachments) {

            # Load the attachment
            $attach.Load()

            # Save the attachment to the predefined location
            $fiFile = New-Object System.IO.FileStream(($downloadDirectory + “\” + $attach.Name.ToString()), [System.IO.FileMode]::Create)       
            $fiFile.Write($attach.Content, 0, $attach.Content.Length)
            $fiFile.Close()
        }
    }
    $more = $frFolderResult.MoreAvailable   # ADDED
    if ($more){ # ADDED
        $view.Offset += 1000    # ADDED
    }   # ADDED
} while ($more) # ADDED

Answer 2

Have a look here: what-is-the-maximal-size-of-an-itemview-in-ews

You'll have to loop over the FindItems using $frFolderResult.MoreAvailable until no more results are returned.