Consolidating emails gmail
2) Click the 3) If you have already enabled 2-Step Verification on your account, skip ahead to the steps below to create a unique App Password for your old Gmail account.
Open your old Gmail account again, find the confirmation email from Google, and copy the confirmation code—then switch back to your button in Gmail, and you can now choose to send emails from your old or your new Gmail address.
9) Click the gear icon, then click Troubleshooting: If the system repeatedly tells you that you’ve entered the wrong username and/or password—but you’re certain that you’ve entered it correctly—it’s erroring because you either have two-step verification enabled on your old account or because Google believes the attempt to access the account is malicious.
The easiest way to resolve the problem is to enable two-step verification (if you haven’t already) and create an app password.
And when you return to new Gmail account's inbox, you’ll see all of the email messages from your old account are being imported into your new account—which could take quite some time if you have a lot of archived emails.
Don't want all of those old emails to fill up your inbox?
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6) Now that you've enabled POP access, you'll need to set your Google account to let POP apps connect to your Gmail account.