How and why should I protect my Office 365 organization from Email Address Internationalization (EAI) attacks?

On 27 December 2017 Microsoft announced that the support for EAI in email has been implemented. This means that the Microsoft cloud now supports EAI email addresses in outlook, email flow, connectors and rules. For now there won’t be any support for adding IDN domains to the platform itself. With this new functionality in Office 365 a new door opens…

Exchange: The security principal specified is already on the permission set

Every once in a while you will find customers running in to the following issue. When they try to get mailbox folder permissions or set mailbox folder permissions  a red error message pops up stating: The security principal specified is already on the permission set. + CategoryInfo          : NotSpecified: (:) [Get-MailboxFolderPermission], CorruptDataException + FullyQualifiedErrorId : [Server=SU8000006141,RequestId=628b5335-6148-4297-8f06-4c607b029737,TimeStamp=15-2-2017 06:46:24] [FailureCategory=Cmdlet-CorruptDataException] BE7556A,Microsoft.Exchange.Management.StoreTasks.GetMailboxFolderPermission + PSComputerName       …

Antispam counter measures explained Part 2: Advanced SPF records,  Best practice and biggest mistakes

Antispam counter measures explained Part 1: How the Sender Policy Framework really works Antispam counter measures explained Part 2: Advanced SPF records,  Best practice and biggest mistakes Antispam counter measures explained Part 3: How DKIM really works and best practice   In Part 1 I explained the basics of SPF and how you can implement the most common scenario`s. After the…

Antispam counter measures explained Part 1: How the Sender Policy Framework really works

Antispam counter measures explained Part 1: How the Sender Policy Framework really works Antispam counter measures explained Part 2: Advanced SPF records, Best practice and biggest mistakes Antispam counter measures explained Part 3: How DKIM really works and best practice   In this first part of “Antispam counter measures explained ” I will start with a detailed explanation of how…

In the last releases of the exchange cu’s for Exchange 2013 and Exchange 2016 Microsoft has introduce a new feature that will support NON-ASCII characters in the local and domain part of email addresses. ( email addresses examples: Пользователь@domain.com  or user@доме.рф). This implementation is being done to have support for more languages in the office 365 service. Microsoft started the implementation…

The Office 365 Hybrid Configuration wizard has been updated to support Exchange 2010. This new wizard comes with the following advantages: An updated user experience that simplifies the hybrid configuration process The error handling experience allows for simple remediation of issues, meaning you can actually read and understand the error Fixes for HCW can happen quickly and are no longer…