# Output file
$OutputFile = "MailboxPermissionsWithSMTPAndName.csv"

# Initialize an array for the results
$Results = @()

# Retrieve all mailboxes (all types)
$Mailboxes = Get-Mailbox -RecipientTypeDetails UserMailbox,SharedMailbox -ResultSize Unlimited

# Loop through all mailboxes
foreach ($Mailbox in $Mailboxes) {
    # Retrieve the primary SMTP address and display name
    $PrimarySmtpAddress = $Mailbox.PrimarySmtpAddress
    $DisplayName = $Mailbox.DisplayName

    # Retrieve mailbox permissions
    $Permissions = Get-MailboxPermission -Identity $Mailbox.Identity

    # Check if specific permissions are set
    if ($Permissions.Count -eq 0) {
        # Add mailbox without additional permissions
        $Results += [PSCustomObject]@{
            DisplayName        = $DisplayName
            MailboxType        = $Mailbox.RecipientTypeDetails
            PrimarySmtpAddress = $PrimarySmtpAddress
            User               = "Default owner"
            AccessRights       = "FullAccess"
            IsInherited        = "N/A"
        }
    } else {
        # Add permissions
        foreach ($Permission in $Permissions) {
            # Filter default permissions such as NT AUTHORITY\SELF
            if ($Permission.User -notlike "NT AUTHORITY\SELF") {
                $Results += [PSCustomObject]@{
                    DisplayName        = $DisplayName
                    MailboxType        = $Mailbox.RecipientTypeDetails
                    PrimarySmtpAddress = $PrimarySmtpAddress
                    User               = $Permission.User
                    AccessRights       = $Permission.AccessRights -join ", "
                    IsInherited        = $Permission.IsInherited
                }
            }
        }
    }
}

# Add mailboxes that may not have displayed permissions
foreach ($Mailbox in $Mailboxes) {
    if (-not ($Results.DisplayName -contains $Mailbox.DisplayName)) {
        $Results += [PSCustomObject]@{
            DisplayName        = $Mailbox.DisplayName
            MailboxType        = $Mailbox.RecipientTypeDetails
            PrimarySmtpAddress = $Mailbox.PrimarySmtpAddress
            User               = "Default owner"
            AccessRights       = "FullAccess"
            IsInherited        = "N/A"
        }
    }
}

# Export the results to a CSV file
$Results | Export-Csv -Path $OutputFile -NoTypeInformation -Encoding UTF8

Write-Host "All mailboxes, permissions, names, and SMTP addresses have been exported to $OutputFile"