Am just running through these instructions (Gmail migration) to begin the process of consolidating some of my standard email user accounts.
https://www.cubebackup.com/docs/tutorials/transfer-gsuite-data-to-another-account/
You might want to think about where an email has been used before eliminating it's account so you can log in to such services and change the email used for those accounts whilst you still have access to the email for them in case you find you need to recover a password for a third party service. Later you can set up aliases for these which is fine if you're staying put with Google or for the short term but if you're migrating away from Google the service you choose may not allow for aliases. If the latter is the case then you will have to say goodbye to those addresses.
+ Logging in first as an G Suite Admin user so I can make an additional user an admin as the original admin user is one of the accounts that needs to bite the bullet in my case as I separated out that responsibility so it wasn't my daily use account.
+ Finding the setting for 'Less secure apps'. Google Admin console menu, > Security > 'Access and data control' > 'Less secure apps'. Set this to 'Allow users to manage their access to less secure apps'.
+ Enable IMAP access for all users. Google Admin console menu, > Apps > 'Google Workspace' > Gmail > 'End User Access'. The first option that opens in the table of settings is 'POP and IMAP access', click the pencil icon on the right hand side if IMAP is not already set to 'ON'.
+ Generate an app password if you have 2 factor authentication or SSO enabled, FOR EACH USER YOU WANT TO MIGRATE FROM. This is required later for the data migration service. Each user will need to log in and click their user icon in top right corner > 'Manage your Google Account' > Security > 'App passwords' > confirm their password when challenged > 'Select app' dropdown menu, 'Other (Custom name)' > enter something like 'migration' > hit the 'Generate' button > copy the password for use later / pass it securely to their admin user.
+ Return to your list of users. Think which accounts you could do without, particularly if you have generic ones such as 'noreply', 'webenquiry', 'listbounces' etc, original admin account if you had split that role out into a separate account even though it may still have related to you, hence the first thing I did above was to make my main user that I want to keep for now, also an admin. Google Admin console menu, > Directory > Users. When you've chosen which accounts need to be migrated click on each account in the Directory > Users list and make a note of the
earliest account creation date. The creation date will be under their name towards the top left of the screen for each user once you click on each user.
+ At this stage you probably want to use a separate browser so you can log in as the first user who's account you want to migrate mail from or get them to. Log in to Gmail for this first user you've chosen to migrate mail from. Click the gear icon toward the top right of the Gmail screen > click 'See all settings' button > 'Forwarding and POP/IMAP' > 'Folder size limits', select 'Do not limit...'. Ensure 'Enable IMAP' is selected e.g. enabled and click 'Save Changes'. Now move to the 'Labels' tab of settings. Make sure each label that you want to migrate mail for is ticked next to each 'Show in IMAP' setting.
+ Back to the browser that you are logged in to G Suite as an admin user. Google Admin console menu, > Account > 'Data migration' > 'SET DATA MIGRATION UP'. Since the Google admin console home screen describes the service as 'Welcome to the Google Workspace Admin Console', we will take that cue of 'Google Workspace' as the service we want to migrate from. So, under 'Select a Migration Source*' dropdown, select 'Google Workspace' and click the START button. On the next screen under 'Migration Start Date' be sure to use the drop down to select the 'Custom Date' option, otherwise it will likely be defaulted to only 'Past 1 year'. Using the account creation date that you noted two bullet points up, you can now enter a meaningful start date. I personally set it to the 1st Jan and the earliest account creation year from the accounts you want to migrate from. Next, select the 'Migration Options', as you so wish, 'Migrate deleted mail', 'Migrate junk mail' & 'Exclude the following folders from the migration (comma separated list). Now click the 'ADD USERS' button.
+ Now add the first user, the one that you logged into as two bullet points up, or got the user to log into to confirm their IMAP settings were configured correctly. On the 'Data Migration' admin console screen, click 'Add user' > enter the 'Source Email' address for this first chosen email account to migrate from. For password, enter the 'app password' generated earlier. In the 'Google Workspace Email' field, start typing the email address of the destination address that you want as the target address to receive the migrated emails. Finally, click the START button to set the migration service to begin running. The data migration screen will update automatically to update the Status column.
Repeat this last step after each user has confirmed their IMAP settings are configured as detailed in the earlier step. Once you / they have confirmed the IMAP settings and created an app password to bypass 2 factor authentication then you can then add each user to the data migration screen using the above step.
You can leave each entry in the data migration table after the migration has completed if further email may be received prior to proceeding to actually deleting those user accounts.
