Now, you can fetch emails from your old Gmail account. by this you can keep safe your important mails on the old email address.
1. Go to the old Gmail account, and click on the setting
2. click on the forwarding and POP/IMAP
3. click on Enable POP for all mail
If you don't know what this should be, leave it on the default setting (which is to leave the copy in the inbox).
4. click on Save Changes and sign out, and go to your new Gmail account
5. Click Again Setting Icon
6. Click on Account Import
7. Check email from other accounts, click on Add an email account.
8. In the pop-up window, enter your old email address, and click Next
9. Once you've chosen all the settings you want, click on Add Account.

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