Beginning February 2, 2026, Duo will require version 4.85.0 or higher of the Duo Mobile app in order to use the Duo Push (or Verified Push) authentication method.
Please update the Duo Mobile app on your phone by February 2, 2026 as soon as possible to avoid disruption.
If you are unable to update to the latest version of Duo, see below for instructions on how to continue accessing your account by using the Duo Mobile passcode and/or other options instead of Duo Push.
How to update the Duo Mobile app
iPhone / iOS
To update Duo Mobile:
- Automatic updates: Settings > Apps > App Store > App Updates
- Also, under "Cellular Data" enable Automatic Downloads
- Manual update: App Store > My Account (On top Right icon) > Available Updates > Duo Mobile > Update
Recent versions of Duo Mobile require iOS 16 or later. If you have an older version of iOS, see Apple's instructions for updating your device: https://support.apple.com/en-us/118575
Android
To update Duo Mobile:
- Automatic updates: Google Play app > Profile > Settings > Network preferences > Auto-update apps
- Manual update: Google Play app > Profile > Manage apps & device > Updates available > See details > Duo Mobile > Update
Recent versions of Duo Mobile require Android 12 or later. If you have an older version of Android, see Google's instructions for updating your device: https://support.google.com/android/answer/7680439?hl=en
How can I access my account if I don't or can't update?
The Duo Mobile app also supports another authentication method called Mobile Passcode, which will continue to work after February 2, 2026.
Using Duo Mobile Passcode
The Duo Mobile passcode can be used as an alternative to verify, especially when there is no internet connection to receive a push notification. To use the Duo Mobile passcode:
- Log in to a Caltech service with your username and password
- When prompted to verify, select "Other Options"
- Select "Duo Mobile passcode"
- Open Duo app on your mobile device
- Select California Institute of Technology
- Enter the 6 digit passcode that appears
Note that the 6-digit passcode is timed, so after 30 seconds, it will refresh. Other Duo authentication methods, such as YubiKey, macOS Touch ID, and Windows Hello, will continue working as usual.
We encourage you to configure more than one authentication method in Duo to avoid interruptions.
More information about all available authentication methods can be found on the IMSS website: /services/security/duo-mfa/duo-authentication-methods
Thank you for taking the time to update your Duo Mobile app. If you have questions or need assistance, please contact the IMSS Help Desk at x3500, [email protected]