Category: Exchange Server

  • Post Tenant To Tenant Migration Calendaring Issues

    Post Tenant To Tenant Migration Calendaring Issues

    When you perform a Microsoft 365 tenant to tenant (T2T) migration and run a migration that is either staged over some time or sometime after the migration has completed you cutover the domains from the old tenant to the new tenant (that is, you were doing a rebrand and the new tenant had a new…

  • Blocking More Obvious Phish – Attachment Filtering

    Blocking More Obvious Phish – Attachment Filtering

    One relatively easy way to block some categories of phishing email is to block the attachment type that is sent with some of these messages. For example, I have had a few of these recently: Hovering over the attachment I see the filename, and it ends .shtml. This attachment is for server-side HTML (SSI includes…

  • Exchange Hybrid Wizard – New Tenants and Missing Errors

    Exchange Hybrid Wizard – New Tenants and Missing Errors

    Rumoured to be fixed end of June 2023 A short blog post on this issue – you see in the Microsoft Exchange Server Hybrid Configuration Wizard logs the following error “Connecting to remote server failed with the following error message: Connecting to remote server outlook.office365.com failed with the following error message : For more information,…

  • Managing Hybrid Exchange Online Without Installing an Exchange Server

    Managing Hybrid Exchange Online Without Installing an Exchange Server

    In April 2022 Microsoft finally released the ability to manage Active Directory synced attributes (Hybrid Identity) to Azure Active Directory for Exchange without a full Exchange Server installation. Instead, you install the Exchange Management Tools (EMT). You need to install Exchange Server 2019 CU12 or later to do this, and you either uninstall your existing…

  • Outlook AutoDetect And Broken AutoDiscover

    Outlook AutoDetect And Broken AutoDiscover

    Those in the Exchange Server space for a number of years know all about AutoDiscover and the many ways it can be configured and misconfigured – if even configured at all. Often misconfiguration is to do with certificates or it is not configured at all because it involves certificates and I thought I was aware…

  • 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…

  • 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…

  • 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…

  • Exchange Transport Rules Corrupt On Installing New Exchange Server Version

    Exchange Transport Rules Corrupt On Installing New Exchange Server Version

    When you install Exchange Server into an existing Exchange organization, your existing configuration typically remains intact and associated with the previous servers and some configuration, that is global in nature, also works across both versions. I can across a scenario where this does not work the other day. The scenario was the installation of Exchange…

  • 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…

  • 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…

  • bin/ExSMIME.dll Copy Error During Exchange Patching

    I have seen a lot of this, and there are some documents online but none that described what I was seeing. I was getting the following on an upgrade of Exchange 2013 CU10 to CU22 (yes, a big difference in versions):      The following error was generated when “$error.Clear();           $dllFile = join-path $RoleInstallPath “bin\ExSMIME.dll”;           $regsvr…

  • 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…

  • Exchange Server Dependency on Visual C++ Failing Detection

    Exchange Server for rollup updates and cumulative updates at the time of writing (Feb 2019) has a dependency on Visual C++ 2012. The link in the error message you get points you to the VC++ 2013 Redistributable though, and there is are later versions of this as well. I found that by installing all versions…