Category: exchange online

  • 550 5.1.8 Access denied, bad outbound sender AS(42003)

    “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…

  • [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…

  • Azure AD Consent For Zoom App Not Applying

    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…

  • iOS and Outlook Mobile and Duplicate Contacts

    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…

  • Why Do Comments In Microsoft 365 Planner Disappear?

    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…

  • Exchange Online Warning On Receipt Of New Email Sender

    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…

  • 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…

  • 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…

  • 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…

  • Enable EOP Enhanced Filtering for Mimecast Users

    Enable EOP Enhanced Filtering for Mimecast Users

    Enhanced Filtering is a feature of Exchange Online Protection (EOP) that allows EOP to skip back through the hops the messages has been sent through to work out the original sender. Take for example a message from SenderA.com to RecipientB.com where RecipientB.com uses Mimecast (or another cloud security provider). The MX record for RecipientB.com is…

  • 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.…

  • 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…

  • How to Use Set-Place to Configure Your Meeting Rooms

    Or Making Your Office 365 Meeting Rooms Accessible or How Wheelchair Users Can Find The Best Meeting Rooms In Your Organization etc. – there are many different titles I can think of for this blog post. They are all to do with setting useful properties against your meeting rooms so that your users can find…

  • Review and Audit Offensive Language in Office 365 Communications

    Review and Audit Offensive Language in Office 365 Communications

    A new feature as of May 2018 in Office 365 is to filter communications based upon the offensive language machine learning filter. This is part of the Supervision settings that have been available for a number of years. The Offensive Language model uses a combination of machine learning, artificial intelligence, and keywords to identify inappropriate…

  • Teams Calendar Fails To On-Premises Mailbox

    Teams Calendar Fails To On-Premises Mailbox

    Article Depreciated: Microsoft now auto-hides the Calendar icon in Teams if your on-premises Exchange Server is not reachable via AutoDiscover V2 and at least Exchange Server 2016 CU3 or later. Once you move your mailbox to Exchange Online (or a supported on-premises version), assuming you did not do any of the below, your Calendar icon…

  • Read Only And Document Download Restrictions in SharePoint Online

    Both SharePoint Online (including OneDrive for Business) and Exchange Online allow a read only mode to be implemented based on certain user or device or network conditions. For these settings in Exchange Online see my other post at https://c7solutions.com/2018/12/read-only-and-attachment-download-restrictions-in-exchange-online. When this is enabled documents can be viewed in the browser only and not downloaded. So…

  • Save Time! Have All Your Meetings End Early [or start late]

    Save Time! Have All Your Meetings End Early [or start late]

    Updated April 22nd 2021 with new global default settings I am sure you have been in a meeting, where the meeting end time rolls around and there is a knock at the door from the people who want the meeting room now, as their meeting time has started and yours has finished. What if you…

  • Too Many Folders To Successfully Migrate To Exchange Online

    Exchange Online has a limit of 10,000 folders within a mailbox. If you try and migrate a mailbox with more than this number of folders then it will fail – and that would be expected. But what happens if you have a mailbox with less than this number of folders and it still fails for…

  • Exchange Move Requests | Large Items | And Setting TCP KeepAliveTime To A Large Value

    I have seen this situation a number of times. A large mailbox (or mailbox and archive) wont move to the target because the process of checking what the changes are in the mailbox take too long, the network or Exchange Server times out the users move and then reports the mailbox is locked. The fix…

  • CRM Router and Dynamics CRM V9 Online–No Emails Being Processed

    This one is an interesting one – and it was only resolved by a call to Microsoft Support, who do not document that this setting is required. The scenario is that you upgrade your CRM Router to v9 (as this is required before you upgrade Dynamics to V9) and you enable TLS 1.2 on the…

  • Read Only And Attachment Download Restrictions in Exchange Online

    Microsoft have released a tiny update to Exchange Online that has massive implications. I say tiny in that it take like 30 seconds to implement this (ok, may 60 seconds then). When this is enabled, and below I will describe a simple configuration for this, your users when using Outlook Web Access on a computer…