---

foreach ($u in $users) {

    $r = Get-Recipient $u -ErrorAction SilentlyContinue

    if ($r) {
        Write-Host "$u - уже Exchange recipient, пропуск" -ForegroundColor Yellow
        continue
    }

    $aduser = Get-User $u -ErrorAction SilentlyContinue

    if (-not $aduser) {
        Write-Host "$u - AD учетная запись НЕ НАЙДЕНА" -ForegroundColor Red
        continue
    }

    try {
        Enable-Mailbox -Identity $u -Database "DB01" -Alias $u -ErrorAction Stop

        Set-Mailbox -Identity $u `
        -UseDatabaseQuotaDefaults $false `
        -IssueWarningQuota 900MB `
        -ProhibitSendQuota 950MB `
        -ProhibitSendReceiveQuota 1GB `
        -ErrorAction Stop

        Write-Host "$u - ГОТОВО" -ForegroundColor Green
    }
    catch {
        Write-Host "$u - ОШИБКА: $($_.Exception.Message)" -ForegroundColor Red
    }
}