Brief description of the service and overview of purpose of Q&A
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A smartphone is the recommended device since the Duo Mobile app provides the greatest level of security and flexibility. The app can receive push notifications for easy, one-tap authentication. Duo Security offers multiple other ways to authenticate with Duo. Besides a smartphone, you can use a tablet, printable USB security key, or printed backup codes or a security key.
What devices are supported by Duo Mobile?
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Duo will work with any cell phone that can receive text (SMS) messages. When adding a device in this mode, first choose "Mobile Phone ,number" and on the next screen enter the phone number. After confirming the phone number , set the phone type as "Other (and cell phones)" and the mobile device will be added.
you will be returned to the main Devices menu.
Now that your phone has been added, whenever you see the Duo Authentication screen, you can select your Mobile phone as the device to use. After choosing Mobile, click on the green "Enter a Passcode" button, then in the blue bar at the bottom, click on the link to "Text me new codes. Take a "Text message passcode" as your authentication option. A new code will be sent via SMS to your phone immediately, just take a look in your phone's text message app. You should see new message with a list of five codes you can use one time each. Enter one of the codes in the box shown below, and you're in!
What do I do if I don’t have my mobile phone with me?
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I will be getting a new phone soon. How can I make a smooth transition to a new phone?
Steps to take for setting up a new phone.
STEP 1. Before wiping your old phone, you should go to go.lehigh.edu/duobackup to print out a new set of one-time-use bypass codes to help with enrolling your new phone. You can use these codes at other times too – if you lose, break, or forget your phone, for example. Keep them in your wallet or purse!
STEP 2. Once you have the print-outcodes, download the Duo Mobile app on your new phone. Then open
You can also search Duo mobile in the Playstore or Apple Store and look for this icon: 
STEP 3. Open a web browser and go to the Duo Device Device Management page.
On the Device Management page, press the green "Enter a Passcode" button, and enter one of the codes you printed out. 
. You may need to authenticate with Duo using the "Bypass Code" option.
STEP 4. You will see your existing iPhone or Android phone in the list of devices. Click the Device Options button next to your phone. 
A Reactivate Duo Mobile button will appear below your phone. 
Clicking on the button will show you a QR code. On your new phone, bring up the Duo Mobile app and tap the Add Account button. It will switch to your phone's camera. Point the camera at the QR code (2d bar code). Lehigh University will now appear in your Duo Mobile app. You're done!
If your phone number will not change, choose "I have a new Phone" and follow the steps. You can scan the QR code or have an activation link texted to you.
If you have a new phone number, choose "Add a device" and follow the steps.
Can I reuse a passcode?
No. Passcodes are only good for a single use.
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How do I add or remove 2FA devices and manage my Duo settings?
Visit www.lehigh.edu/account and follow the “Two-factor authentication with Duo” link. You will first need to authenticate with Duo, after which you will see the settings screen as pictured below.
Click the "+ Add another device" link, then choose the type of device you will be adding. 
If you're adding your office phone, select Landline. 
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I use a landline for Two-Factor Authentication (2FA), and I’m going away for a week. Can I still use the service?
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