This update also includes new daylight saving time (DST) updates for Exchange Server 2016. For more information about DST, see Daylight Saving Time Help and Support Center.
Known issues in this cumulative update
- In multidomain Active Directory forests in which Exchange is installed or has been prepared previously by using the /PrepareDomain option in Setup, this action must be completed after the /PrepareAD command for this cumulative update has been completed and the changes are replicated to all domains. Setup will try to run the /PrepareAD command during the first server installation. Installation will finish only if the user who initiated Setup has the appropriate permissions.
- If you are upgrading from Cumulative Update 13 for Exchange Server 2016 or a later cumulative update for Exchange Server 2016 to Cumulative Update 15 for Exchange Server 2016, then there’s no need to run the /PrepareAD or /PrepareDomain. No additional actions (prepareAD, prepareDomain, or assigning permissions) are required.
- If you has ever skipped a Cumulative Update (for example, you are upgrading from an earlier version before Cumulative Update 13 for Exchange Server 2016), or this is a first Exchange Server installation in the AD, then this Known Issue section should be taken care of.
a. About the /PrepareDomain operation in multidomain:
The /PrepareDomain operation automatically runs in the Active Directory domain in which the /PrepareAD command is run. However, it may be unable to update other domains in the forest. Therefore, a domain administrator should run the /PrepareDomain in other domains in the forest.
b. About the permission question:
As the /PrepareAD is triggered in Setup, if the user who initiates Setup isn't a member of Schema Admins and Enterprise Admins, the readiness check will fail and you receive the following error messages:
To avoid the error messages, either the user should join Schema Admins and Enterprise Admins groups, or another user in Schema Admins and Enterprise Admins groups manually runs the /PrepareAD for this Cumulative Update first. Then the Exchange admin user can start Setup.
- Autodiscover Event ID 1 after installing Cumulative Update 14 for Exchange Server 2016. For more information, see KB 4532190.
Issues that this cumulative update fixes
- 4515256 “The function cannot be performed…” error when you send a message that’s open for a long time in Exchange Server 2016
- 4528693 Get-CalendarDiagnosticLog is proxied for queries within the same forest in Exchange Server 2016
- 4523519 Set-SendConnector doesn't work for Exchange Server in hybrid scenarios with Edge Server installed
- 4528690 Can’t move or delete folder in Outlook online mode if the destination has a folder with the same name in Exchange Server 2016
- 4528687 NotificationClient logs aren't purged and consume lots of disk in Exchange Server 2016
- 4528689 Outlook on the web shows MailTip when recipients equal the large audience size in Exchange Server 2016
- 4528688 Only one recipient shows when saving draft by using Exchange ActiveSync version 16.0 in Exchange Server 2016
- 4528695 Event ID 4009 when using SubjectOrBodyMatchesPatterns on Edge server in Exchange Server 2016
- 4528694 Can't open .ics file in Outlook on the web in Exchange Server 2016
- 4528692 "A parameter was specified that isn't valid” error when creating transport rule in Exchange Server 2016
- 4515257 Hash mismatch is reported for Exchange DLLs in the bin directory of Exchange Server 2016
- 4528696 Exchange PowerShell cmdlets take longer time to run in Exchange Server 2016
- 4532747 Address list separation not working for a user without a mailbox in Exchange Server 2016
- 4523171 Description of the security update for Microsoft Exchange Server 2019, 2016, and 2013: November 12, 2019
Get Cumulative Update 15 for Exchange Server 2016
- The Cumulative Update 15 package can be used to run a new installation of Exchange Server 2016 or to upgrade an existing Exchange Server 2016 installation to Cumulative Update 15.
- You don't have to install any previously released Exchange Server 2016 cumulative updates or service packs before you install Cumulative Update 15.
Cumulative update information
This cumulative update requires Microsoft .NET Framework 4.8.
A component that's used within Exchange Server requires a new Visual C++ component to be installed together with Exchange Server. This prerequisite can be downloaded at Visual C++ Redistributable Packages for Visual Studio 2013. For more information, see KB 4295081.
For more information about the prerequisites to set up Exchange Server 2016, see Exchange 2016 prerequisites.
You may have to restart the computer after you apply this cumulative update package.
You don't have to make any changes to the registry after you apply this cumulative update package.
After you install this cumulative update package, you can't uninstall the package to revert to an earlier version of Exchange Server 2016. If you uninstall this cumulative update package, Exchange Server 2016 is removed from the server.
For more information about the deployment of Exchange Server 2016, see Release notes for Exchange 2016.
For more information about the coexistence of Exchange Server 2016 and earlier versions of Exchange Server in the same environment, see Exchange 2016 system requirements.
For more information about other Exchange updates, see Exchange Server Updates: Build numbers and release dates.