Known issues and troubleshooting for Two-Step Login (Duo) at IU

As of November 2, 2017, CAS logins for all IU faculty, staff, students, retirees, and affiliates will require Two-Step Login (Duo). This includes both personal and group or departmental accounts. For more, see About using Two-Step Login (Duo) every time I log into CAS.

Following is information about known university-wide issues, troubleshooting steps, and common questions for Two-step login (Duo) at Indiana University.

Issue Description Workaround Last updated
Error message "Incorrect passcode. Please try again." after correctly using a passcode from a token

You may see the "Invalid Passcode" error for any of these reasons:

  • You haven't used your token for more than a month.
  • The token went out of sync after the button was pressed repeatedly over a short period of time or if the numbers generated were not used. This can happen if you keep it in your pocket or on a keyring.
  • You have the token upside down. When the token is right side up, you should only see digits (not letters), and the word "DUO" and the button should be on the left side.
  • You have multiple devices and attempted to use the token. If you have a phone, it should be your default device. To use the token, choose it from the drop-down box at the DUO prompt.
Attempt to log in three times in a row with a new code each time to resync your token to the Duo servers. If after the third attempt, it still fails, contact your campus Support Center. August 31, 2016
Duo authentication prompt does not load when attempting to sign into Chrome with a Google at IU account The web page does not load the Duo authentication prompt and instead displays a blank space where the prompt should appear. N/A June 13, 2017
YubiKey 4 Nano is not recognized A YubiKey 4 Nano is connected to your computer, but it is not being recognized by Duo or other YubiKey-supported services. Check to make sure the device is inserted the correct way into your computer (e.g., unplug the device, turn it over, and plug it back in). June 9, 2017
In China, Duo Mobile for Android cannot be downloaded from the Google Play Store In China, the Google Play Store is not available. You can download the Android Duo Mobile app directly from Duo's website instead of using the Google Play Store.

To install the app, you will need to enable a "sideloading" feature in your Android device. Sideloading means installing an app from a source other than the Google Play store.

To enable sideloading in your Android device:

  1. From the Home screen, press Menu. Tap Settings, then Security, and then check Unknown sources.
  2. Download the Duo Mobile app directly.

    You will need to use your Android device's File Manager app to locate and install the downloaded app.
Note: Duo Mobile push notifications require Google Play Services. Google Play Services are not available in China, so you will have to "fetch" Duo Mobile push notifications by opening the Duo Mobile app and swiping down.
May 15, 2017
iOS 7 Duo Mobile support ending on March 1, 2017 Duo Mobile support for Apple devices running iOS 7 or earlier will end on March 1, 2017. Duo Mobile for iOS 7 will also be unavailable for download. Duo authentication in the form of phone calls and SMS text messaging will continue to be available for these devices. February 24, 2017
Blank or flashing screen appears when attempting to authenticate to Duo Using older versions Chrome with the LastPass extension may prevent the Duo interface from loading. Update Chrome to the latest version. February 3, 2017
Duo authentication prompt does not load The web page does not load the Duo authentication prompt and instead displays a blank space where the prompt should appear. Dragon NaturallySpeaking speech recognition software sometimes causes this issue. Temporarily disabling this software allows the Duo authentication prompt to load correctly. October 17, 2016
Changes not saved when renaming device If you click Back to login without clicking Save, your changes will not be saved. Follow the instructions in Renaming a device in Managing your Two-Step Login (Duo) devices and settings. September 6, 2016
"Undefined" error message If the Duo two-factor authentication screen displays an "Undefined" error when you are trying to send a login request, most likely your session timed out after staying idle for too long. Refresh the page or open a new browser window, and then try again. If the problem persists, contact your campus Support Center for help. September 6, 2016
Account is locked Your account may be locked after repeated failed login attempts. If your account is locked, contact your campus Support Center to request that it be unlocked. September 6, 2016
Error message "Denying unknown user" When using Duo to log into an Indiana University service, if you have not finished enrolling, you may see the error message "Denying unknown user." Try to complete the process to enroll your mobile device with Duo. August 18. 2016
If you use Two-Step Login (Duo) every time you log into CAS, the Duo screen cut is off during Office 365 account sign-in When signing into your Office 365 account using any Office desktop application for Windows, the Duo Authentication screen does not completely fit in the window and some options are cut off the screen. Press Tab on your keyboard to scroll down and view the rest of the Duo Authentication options. August 10, 2016

For help, contact your campus Support Center.

This is document bfnf in the Knowledge Base.
Last modified on 2017-06-13 15:56:40.

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