Exchange

I had this weird issue with a Exchange Server environment: The company had an Exchange Server 2016 DAG and migrated all User Mailboxes to Exchange Online. I then installed a fresh Exchange Server 2019 for Recipient Management and SMTP-Relay. To use the Exchange Server 2019 Hybrid License, I did not create a Mailbox Database. I removed all remaining System Mailboxes and Arbitration Mailboxes from the Exchange 2016 Servers. I decomissioned the DAG and uninstalled Exchange from the old Servers. ...

I had an issue with a broken Exchange Server 2016 CU23. Or rather it was not fully installed. It was just a test environment, but I thought it would be useful or interesting to drill down on that issue. I’ll guide you through my troubleshooting steps / thought process. ...

If you’re using Microsoft Booking in your Microsoft 365 Tenant, you might want to list all of the Booking calendars. Booking uses Exchange Online Mailboxes in the background. Every Booking Calendar has a corresponding Mailbox of the type “SchedulingMailbox”. If an user gets assigned “Administrator” for a Booking Calendar, they get “FullAccess” permissions for the Scheduling Mailbox. List all Booking Calendars with permission I wrote a PowerShell script to list all the Booking Mailboxes with the users that have access. ...

If you have Auto-Expanding Archives for Exchange Online Mailboxes enabled, you might want to find out, if it actually provisions additional storage. In the Exchange Admin Center (EAC), open the info pane of the user’s mailbox. Click on “Manage mailbox archive”. An Auto-Expanding Archive provisions more Archive storage space, if needed. Default Archives have 100 GB of storage available. If the archive is already bigger than 100 GB, we must have additional storage. ...

When the first users logged into Office 365 with his iPhone to sync his Contacts and Calendar, he got this dialogue: Need admin approval Apple Internet Accounts Apple Internet Accounts needs permission to access resources in your organization that only an admin can grant. Please ask an admin to grant permission to this app before you can use it. By the way, the app used to be called “iOS Accounts” and was apparently renamed in early 2020. However, the previous AppID has remained the same. ...

At the end of the Hybrid Configuration Wizard (HCW) I received the following warning message: HCW8064 - The HCW has completed, but was not able to perform the OAuth portion of your Hybrid configuration. If you need features that rely on OAuth, you can try running the HCW again or manually configure OAuth using these manual steps. The link “more information” links to https://support.microsoft.com/en-us/help/3089172/hcw-has-completed-but-was-not-able-to-perform-the-oauth-portion-of-you. If you lookup what OAuth is used for, this article comes up. There you can read OAuth is needed for cross-premises eDiscovery searches. Since these functions were not relevant in the project, I ignored them for the time being. By the way, running HCW again did not set up OAuth properly in this case. But sometimes you can easily fix a issue like this by re-running HCW. ...

If you’re wondering when an Exchange mailbox got created, you will most likely stumble over the Active Directory user attribute MSExchWhenMailboxCreated. You can get the value using PowerShell or ADUC with advanced features enabled. 1 Get-ADUser -Properties MSExchMaiboxWhenCreated MSExchWhenMailboxCreated contains not the full truth That could almost be the end of the story. BUT that attribute is not what you might think. The attribute gets only propagated the FIRST time the user gets a mailbox. If that users mailbox was disabled and then recreated later, the timestamp of the first mailbox creation retains. ...

By default, the “Calendar” folder in Exchange 2013 Room Mailboxes has the “LimitedDetails” permission for the “Standard” security principal. Therefore, if no other permissions are configured, users cannot view details for appointments in this room. For better usability in Outlook, the “Reviewer” permission is more suitable. This allows items to be listed and details to be displayed. If required, the CalendarProcessing can be adjusted so that details such as the description and subject of the appointment are not saved in the room mailbox. Whether all this makes sense always depends on the environment. ...

Outlook Certificate Warning after Office 365 Migration Security Alert: svr1.example.com The security certificate has expired or is not valid yet I recently received a request from a customer who still received certificate warnings (expired certificate) for the old Exchange Server after migrating to Office 365. Since I was not involved in the migration, I had to get an overview first: The On-Premise Exchange Server 2010 was still online - of course, otherwise a certificate warning would hardly have appeared. However, not all users received this message. This affected migrated users as well as users whose mailboxes were created directly in Office 365. ...