EX16-MB-000310 - Exchange Mail quota settings must not restrict receiving mail.
Mail quota settings control the maximum sizes of a user's mailbox and the system's response if these limits are exceeded. Mailbox data that is not monitored against a quota increases the risk of mail loss due to filled disk space, which can also render the system unavailable. Failure to allow mail receipt may impede users from receiving mission-critical data.
Open the Exchange Management Shell and enter the following command: Set-MailboxDatabase -Identity <'IdentityName'> -ProhibitSendReceiveQuota Unlimited Note: The <IdentityName> value must be in single quotes. or Enter the value as identified by the EDSP that has obtained a signoff with risk acceptance.