When attempting to activate Duo Mobile or receive a Duo Push on an iOS device, you may see an error message such as one of the following:

• "Invalid Certificate - the certificate provided is invalid"
• "Unknown error canceled (-999)"
• "An SSL error has occurred and a secure connection to the server cannot be made. (-1200)"

These error messages indicate that there is an issue with your device's network connection.  Please try one of the solutions below to see if it resolves your issue.

Connect to a Different Network

If you are on campus:

1. Make sure your device is connected to Eduroam. The ncsu network is unsecured; unsecured networks can cause errors when attempting to approve push notifications.
2. Try switching to mobile data.

If you are off-campus:

1. Try changing networks.  If you are connected to an unsecured, public Wi-Fi network, this can cause Duo push notifications to fail.
2. Try switching to mobile data.

Generate a Passcode

Instead of logging in with push notifications, you can also log in using passcodes.

Other Solutions

• Restart your device.
• Ensure that the device's time is set to "Set automatically" at Settings > General > Date & Time.
• Reactivate Duo Mobile.
• Resend the activation link.

If all of the above options do not work, please contact the NC State Help Desk at 919-515-4357 or help.ncsu.edu.