Click Settings on your iPhone.
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Click Passwords and Accounts.
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Click Add Account.
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Click Microsoft Exchange.
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Enter your Email, change the description (optional), then click Next.
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Click Sign In.
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Enter your email, password, and Click click Sign In.
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You’ll be re-directed redirected to the Duo app. Use your preferred method of authentication.
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Click Continue.
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Choose the options you’d like to turn on or off, then click Save.
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