Administrator setup for GAMMO

This page is for administrators who plan to deploy Google Apps Migration for Microsoft® Outlook (GAMMO) to their users. To install GAMMO yourself and begin using it, you should instead see the Google Apps Migration user help.


GAMMO lets individual users migrate their own calendar, contact, and email data from Microsoft Exchange or from local PST files to a Google Apps account. Administrators can use the command-line version of the utility to migrate data on behalf of a single user.

Note: Only personal contacts are migrated for each user. In order for your Global Address List, including shared contacts, to be available to users, an administrator has to migrate that data first with a utility like Google Apps Directory Sync.

Windows system requirements for client machines

Each user's machine that runs the migration utility needs to have the following minimum configuration:

  • Microsoft Windows®:
    Windows XP (32 bit) SP3 
    Windows Vista (32 bit) SP1 
    Windows Vista (64 bit) SP1 
    Windows 7 and 8 (32 and 64 bit)
    Windows 10 (32 and 64 bit)

Regardless of which version of Windows you are using, we recommend that you upgrade to the latest patches for that version.

  • Microsoft Outlook 2003 SP3 
    Microsoft Outlook 2007 SP2 (or SP1 with hotfix
    Microsoft Outlook 2010 (32 and 64 bit)
    Microsoft Outlook 2013 (32 and 64 bit)
    Microsoft Outlook 2016 (32 and 64 bit)
Provision your users in Google Apps

Before your users can migrate data, you have to provision accounts for them in Google Apps. See create a new user for details. Each user, including any Google Apps administrators, must also sign in to their Google Apps account at least once, to accept the Google Terms of Service.

In addition to provisioning user accounts in Google Apps, you can also:

  • Create nicknames for your users that match aliases they had on your Exchange Server
  • Create groups that match the mailing lists on your Exchange Server
  • Add domain aliases


Migrate your Shared Contacts

Before your users migrate their data, you should migrate your shared contacts to Google Apps so that your users have immediate access to your full address list.

For information about migrating contacts, see:

Install Google Apps Migration for Microsoft Outlook

After you have configured Google Apps, verified the Windows system requirements on each client machine, provisioned your users in Google Apps, and migrated your shared contacts, your next step is to install Google Apps Migration for Microsoft Outlook on each user's computer.

You have two options for installation:

  • Push an .msi to your users, and let them use the Run Advertised Programs option in the Windows Control Panel. Download the .msi file below (be sure to pick the correct version for your users' version of Outlook). For information on implementing the .msi file, consult your Windows documentation.

    Download the GoogleAppsClientMigration.msi:
  • Let your users get the utility from the GAMMO download page, and complete the installation themselves.

To run the installer:

Double-click OutlookMigrationSetup.exe, then click Run.

The utility is installed in the following location:
C:\Program Files\Google\Google Apps Migration\ClientMigration.exe.

Perform migrations

Run only one instance of the utility on a computer, and run only one instance of the utility for each user.

For detailed information about using the utility to perform migrations, see the GAMMO Help Center.

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