PowerShell Scripts to Convert OST to PST for Free

Converting OST to PST files can be a crucial task for users dealing with Outlook data recovery or migration. While several third-party tools offer this functionality, PowerShell scripts provide a free, flexible way for advanced users to automate the OST to PST conversion process. These scripts are especially helpful in enterprise environments where bulk conversions and automation are essential.

Free PowerShell method to Export OST into PST

PowerShell itself does not offer direct support for OST to PST conversion, but it can be used in combination with Outlook’s COM object or other built-in Windows tools to access mailbox data. For example, a script can automate the export process by launching Outlook, accessing the OST file through a configured profile, and saving data to a PST file.

Users must have Outlook installed on the system and the profile configured to access the OST file.

# Load Outlook COM object

$outlook = New-Object -ComObject Outlook.Application

$namespace = $outlook.GetNamespace("MAPI")

# Select the mailbox Inbox (you can change folder name)

$folder = $namespace.GetDefaultFolder([Microsoft.Office.Interop.Outlook.OlDefaultFolders]::olFolderInbox)

# Output CSV file

$csvPath = "C:\OST-Export.csv"

# Create array to store email data

$result = @()

foreach ($item in $folder.Items) {

    if ($item -is [Microsoft.Office.Interop.Outlook.MailItem]) {

        $result += [PSCustomObject]@{

            Subject       = $item.Subject

            Sender        = $item.SenderName

            SenderEmail   = $item.SenderEmailAddress

            To            = $item.To

            CC            = $item.CC

            Received      = $item.ReceivedTime

            Body          = $item.Body

        }

    }

}

$result | Export-Csv -Path $csvPath -Encoding UTF8 -NoTypeInformation

Write-Host "Export completed. CSV saved to $csvPath"

Steps to import CSV file into Outlook and Export in PST

1. Import CSV into Outlook:
Outlook → File → Open & Export → Import/Export → Import from another program or file → CSV
2. Export to PST:
Outlook → File → Open & Export → Import/Export → Export to a File → PST

Conclusion

Though this method may require technical expertise, it offers a cost-effective solution without relying on external software. Always test scripts in a secure environment before using them in live systems to avoid data loss. For businesses or users looking for a no-cost way to manage OST data, PowerShell-based approaches provide an efficient and customizable option when used carefully.

Convert OST file using Outlook

OST Converter Tool