Notice: This website is an unofficial Microsoft Knowledge Base (hereinafter KB) archive and is intended to provide a reliable access to deleted content from Microsoft KB. All KB articles are owned by Microsoft Corporation. Read full disclaimer for more details.

"Forest 'New Forest' needs to be updated" warning message when you try to create a federation trust between the on-premises Exchange environment and Office 365

View products that this article applies to.


When you try to create a federation trust between the on-premises Microsoft Exchange environment and Microsoft Office 365, you receive the following warning message:

Forest 'New Forest' needs to be updated

However, when you click the link to Microsoft Update to download the latest version, Microsoft Update reports that your current version of the Exchange Management Console is up to date.

↑ Back to the top


This issue occurs if the current on-premises Exchange Management Console (EMC) is incompatible with the version of the EMC that's used by the Datacenter edition of Exchange in Office 365.

↑ Back to the top


Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756 How to back up and restore the registry in Windows

To work around this issue, modify the following registry subkey on the server where you want to run the Exchange Management Console. This change prevents a version comparison. To do this, follow these steps:
  1. Open Registry Editor.
  2. Locate and then right-click the following registry subkey:

  3. Click New, and then click String Value.
  4. Type EMC.SkipVersionCheck for the new string value, and then double-click the new string value.
  5. Under Value, type true, and then click OK.
  6. Exit Registry Editor.

↑ Back to the top

More information

Still need help? Go to the Office 365 Community website.

↑ Back to the top

Keywords: KB2491947, o365m, o365022013, o365e, o365a, o365

↑ Back to the top

Article Info
Article ID : 2491947
Revision : 16
Created on : 7/9/2014
Published on : 7/9/2014
Exists online : False
Views : 59