This document will help you migrate email from your personal GMail to your university M+Google account using the open-source Gmvault tool. Gmvault is a command-line tool and is not supported by U-M. It also requires you to use your own computer to complete the migration. The migration copies (syncs) messages from your source accounts to the local drive on your computer. After the sync is complete, another process restores the messages from your local drive to your target account.
Depending on the size of your mailbox, the migration can take many hours to complete. Before beginning, follow these steps:
Because Gmvault runs on your local computer, that computer needs to be powered on and awake for the entire migration process. To prevent your computer from sleeping, you may need to temporarily disable the power saving features. You may also consider using an app to prevent your computer from sleeping
Before beginning a migration, verify that you have enough space on your hard drive. To view how much space your mail will require, open Drive (not GMail). At the bottom-left of the Drive window, the total amount of shared data in your account is displayed. Hover over the Manage link to see how much data Gmail will require.
To verify that both of your accounts have IMAP enabled, follow these steps.
Installers are available for Windows, Mac, and Linux. Visit the Gmvault download page to locate your computer’s installer and follow the installation instructions.
The migration process generally occurs in two phases: syncing and restoring. Both phases will ask you to sign into the appropriate Google account and authorize Gmvault to access your Mail account. It is important that you are signing into the appropriate account for each phase. Sign out of any active Google sessions in your default browser before beginning.
Once you authorize Gmvault for a particular account, Gmvault stores that authorization on your computer so it can automatically authenticate later. These credentials are stored in $HOME/.gmvault (or %HOME%/.gmvault for Windows).
Gmvault backs up your complete gmail account by default into $HOME/gmvault-db (or %HOME%/gmvault-db for Windows)
When you are done migrating your mail, you can revoke Gmvault’s access to your accounts. To do so, open your Account Permissions page for each account, locate the items titled “Gmvault - Backup your Gmail account”, click it, and then click the Revoke access button in the right column.
Gmvault also has advanced commands not covered in this document that allow syncing specifics portions of your mail account, local backups, and maintenance of the synced email on your computer. While these topics aren’t covered here, see Gmvault’s documentation if you’re interested in using these features.