In addition to creating a new client from an email, you can also connect an email to an existing client.
Find and open the email in your emails list, click the three-dot icon at the top, and choose Associate email with client.
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Choose the client the email is linked with and click Add, or you can create a new client from the email.
Search for the client and check the client box, to associate the email.
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Once added, the email appears in the Emails.
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See also: