Configure message throttling for your organization with recipient rate limit of 5000 and message rate limit of 20

Task: Configure message throttling for your organization with recipient rate limit of 5000 and message rate limit of 20

Use this command:

New-ThrottlingPolicy -Name fightspam -RecipientRateLimit 5000 -MessageRateLimit 20  

Now Apply policy to particular mailbox:

Set-Mailbox -Identity user_alias -ThrottlingPolicy fightspam

Use this command to apply to an Organizational Unit:

get-mailbox -OrganizationalUnit 'domain/OU' -resultsize unlimited | set-mailbox -Throttling

Policy fightspam