if (-NOT (Get-Module -ListAvailable -Name ExchangeOnlineManagement)) {

    Install-Module -Name ExchangeOnlineManagement

}

Import-Module ExchangeOnlineManagement

$admin = Read-Host "Exchange admin email or UPN"

Connect-ExchangeOnline -UserPrincipalName $admin

$users = Get-User

$senders = @(
    'docunotice.com',
    'messagecenters.net',
    'securedinbox.net',
    'notificationhub.net',
    'secure-access.info',
    'login-updates.com',
    'updateportals.com',
    'accountverifies.com',
    'auth-check.page'
)

foreach($user in $users){

    $out = 'Adding Trusted Senders to {0}' -f $user.UserPrincipalName

    Write-Output $out

    Set-MailboxJunkEmailConfiguration $user.UserPrincipalName -TrustedSendersAndDomains @{Add=$senders}

}

Write-Output "Finished!"