Uninstall Outlook 2010 and install a previous version


Applies to: Office 2010

Topic Last Modified: 2011-10-18

In some circumstances, you might need to restore a group of users to a previous installation of Microsoft Outlook after an upgrade to Microsoft Outlook 2010. To do this, you remove Outlook 2010, and then reinstall the previous version of Outlook. You must also re-create the users' Outlook profiles.

In this article:

  • Overview

  • Uninstall Outlook 2010 by using the OCT

  • Install a previous version of Outlook


If you installed Outlook 2010 by using the Office Customization Tool (OCT), you remove Outlook by using the OCT. In the OCT, you select Office 2010 from the list of options and set the feature installation state to Not Available to uninstall it. For more information about the OCT, see Customize Office 2010.

If you installed Outlook 2010 from a stand-alone product CD, you must run Setup with the /uninstall command-line option on each computer to uninstall Outlook. For more information, see Setup command-line options for Office 2010.

Because of the changes in Outlook 2010 that allow for multiple Microsoft Exchange Server e-mail accounts, user profiles that are upgraded to Outlook 2010 will not work if you uninstall Outlook 2010, reinstall a previous version of Outlook like Office Outlook 2007, and then attempt to start Outlook by using the same user profile. You must configure and deploy new profiles for users when you reinstall a previous version of Outlook.

Effect on Outlook settings

Settings that you specify in Outlook 2010 are not retained when you revert to a previous installation of Outlook. Outlook settings will revert to default values or will be set as they were before you installed Outlook 2010 (depending on the setting).

Rules are saved in the Outlook store and are not affected by uninstalling and reinstalling Outlook.

Effect on .pst files

Outlook personal data files (.pst) are not affected by installing or uninstalling Outlook 2010.

If users have Unicode .pst files and are reinstalling an earlier version of Outlook that does not support Unicode .pst files, they can copy the information into an Outlook 97–2002 Personal Folders file. To do this, create a data file in the older Outlook 97–2002 Personal Folders file format. Then import items into that file from the Unicode data file. There is no automatic procedure to convert files from one format to the other.

Uninstall Outlook 2010 by using the OCT

To remove Outlook 2010 by using the Office Customization Tool

  1. To start the OCT, from the root of the network installation point, run the following command:

    \\server\share\setup.exe /admin

  2. To edit an existing Setup customization file (.msp), in the Select Product dialog box, click Open an existing Setup customization file. Or to create a new customization file, select the Office suite that you want to customize, and then click OK.

  3. In the navigation pane, select Set feature installation states.

  4. In the center pane, expand the Microsoft Office tree, and then right-click Microsoft Outlook.

  5. Select the installation option Not Available. To prevent users from reinstalling Outlook, select Hidden and Locked. The application name is displayed as [H] [L] Microsoft Outlook.

  6. After you have finished all the customizations, save the Setup customization file (.msp), and then exit the OCT.

  7. Deploy and apply the Setup customization file (.msp) to users' computers.

Install a previous version of Outlook

When you have removed Outlook 2010, reinstall the previous version of Outlook. As part of the installation, configure new profiles for users. For example, set options for Office Outlook 2007 by using the OCT or for Office Outlook 2003 or earlier versions by using the Custom Installation Wizard. Or, you can configure new profiles by distributing an Outlook profile (.prf) file.