“Your message couldn’t be delivered because you weren’t recognized as a valid sender. The most common reason for this is that your email address is suspected of sending spam and it’s no longer allowed to send email. Contact your email admin for assistance.” This is an error you get when your anti-spam “outbound” policy restricts… Continue reading 550 5.1.8 Access denied, bad outbound sender AS(42003)
[New] External Email Notification in Exchange Online
This is a new feature released in March 2021 that adds support in Outlook (Mac, OWA, Mobile) for the display of the external status of the sender – note at the time of writing it does not add this feature to Outlook for the PC. This should be used to replace the way this has… Continue reading [New] External Email Notification in Exchange Online
Azure AD Consent For Zoom App Not Applying
This is a issue where you enabled Admin Approved Consent in Azure AD (as you should) and you require apps that have high data access rights to be approved. The Zoom add-in/desktop app falls into this category as it requires write access to your calendar and your contacts in Exchange Online. But if you set… Continue reading Azure AD Consent For Zoom App Not Applying
iOS and Outlook Mobile and Duplicate Contacts
Of the back of a few conversations recently on having duplicate contacts in the iOS platform because of syncing via multiple different routes or devices I decided to try to reproduce the issues and see what I could work out. I looked on my test iPhone to see if I could see any duplicates and… Continue reading iOS and Outlook Mobile and Duplicate Contacts
Removing a Default Sensitivity Label
In Microsoft 365 Sensitivity Labels you can have a label policy that requires that all content is labelled. If you enable this and then later decide this is not for you, you can republish your label policy and disable the default label and the require label policies. That is, your settings start like this: And… Continue reading Removing a Default Sensitivity Label
Unable To Update Defender Preferences
I was trying to add Microsoft Defender exceptions via PowerShell to a clients server (Windows Server 2016 if that matters) the other day and it was always failing – the error was: This was returning “Failed to modify preferences” on the Add-MpPreference cmdlet and the error code 0x80070073 To fix I needed to uninstall Windows… Continue reading Unable To Update Defender Preferences
Why Do Comments In Microsoft 365 Planner Disappear?
So first you need an Exchange Online mailbox for comments to work. Comments to the tasks of Plans are stored in the Microsoft 365 Group mailbox, and you need an Exchange Online mailbox to access the M365 Group mailbox. Behind the scenes, or actually not that behind the scenes, the process for comments is as… Continue reading Why Do Comments In Microsoft 365 Planner Disappear?
Exchange Online Warning On Receipt Of New Email Sender
Released recently to no fanfare at all, Microsoft now has a SafetyTip that appears if you receive email from a first time recipient. Most often phish emails will come from an address you have never received email from before, and sometimes this email will try to impersonate people you communicate with or are internal to… Continue reading Exchange Online Warning On Receipt Of New Email Sender
Microsoft 365 From A Raspberry Pi 400 Personal Computer
So my new computer arrived today, its a keyboard and a few cables, and as my first computer was a ZX Spectrum when I was 14, this brings back a few memories. But, is it usable today with services such as Microsoft 365? Lets see… First, the actual computer is in the keyboard, but its… Continue reading Microsoft 365 From A Raspberry Pi 400 Personal Computer
Enabling Better Mail Flow Security for Exchange Online
At Microsoft Ignite 2020, Microsoft announced support for MTA-STS, or Mail Transfer Agent Strict Transport Security. This is covered in RFC 8461 and it includes making TLS for mail flow to your domains mandatory whereas it is currently down to the decision of the sender. You can publish your SMTP endpoint and offer the STARTTLS… Continue reading Enabling Better Mail Flow Security for Exchange Online
Reporting on MTA-STS Failures
This article is a follow up to the Enabling Better Mail Flow Security for Exchange Online which discusses setting up MTA-STS and in this article we cover the reporting for MTA-STS. To get daily reports from each sending infrastructure to receive reports on MTA-STS you just create a DNS record in the following format: It… Continue reading Reporting on MTA-STS Failures
Enable EOP Enhanced Filtering for Mimecast Users
Blog post updated March 2020 to include more specific IP ranges for all Mimecast regions and to fix an issue where the email sender is also using the same Mimecast region as yourself and the risk of SPF failures. Enhanced Filtering is a feature of Exchange Online Protection (EOP) that allows EOP to skip back… Continue reading Enable EOP Enhanced Filtering for Mimecast Users
Mail Flow To The Correct Exchange Online Connector
In a multi-forest Exchange Server/Exchange Online (single tenant) configuration, you are likely to have multiple inbound connectors to receive email from the different on-premises environments. There are scenarios where it is important to ensure that the correct connector is used for the inbound message rather than any of your connectors. Here is one such example.… Continue reading Mail Flow To The Correct Exchange Online Connector
What Is The Value of enrollmentProfileName
In Microsoft EndPoint Manager there are a few different device registration scenarios that make use of a property called device.enrollmentProfileName. To find and apply other settings (apps, config, etc) to these devices later on you need to have a Dynamic Device Group based on this property. The problem is the value of the property is… Continue reading What Is The Value of enrollmentProfileName
Free Web Content Filtering With Microsoft Defender ATP
Well free as in you need an MDATP licence first, but as this used to be an add on feature on top of MDATP with an additional cost, this is now effectively free once you are licensed for MDATP. The feature enables your organisation to track and regulate access to websites based on their content… Continue reading Free Web Content Filtering With Microsoft Defender ATP
Force Mailbox Migration With Bad Items To Complete (2020)
It used to be easy to complete an Exchange Server > Exchange Online move request that had bad items, but this has changed recently. In the last short while Move Requests (and Migration Batches) have begun to include a property called DataConsistencyScore If the result from the above is “Investigate” then you will not be… Continue reading Force Mailbox Migration With Bad Items To Complete (2020)