Problem with registering for Duo with international numbers

There may be cases where you are unable to register a mobile device with a international number for Duo because you do not receive the initial text with link that will connect the mobile device to your Duo.

If you are unable to obtain a Yubikey in the meantime and will have the international number for an indefinite period, please register the international mobile phone as a landline device (as opposed to mobile). When registering, input the phone number starting with the country code. You MUST add + before the country code (e.g., +1 for US/Canada, +44 for United Kingdom).

With this method, you will get a phone call asking you to authenticate rather than the text with the link.

Similarly, you can register your smartphone as a tablet device to use push notifications over the internet, or the 6-digit code generated by the Duo Mobile App which requires no internet access.

Also, please use the "Remember me for 30 days" option, so the you can avoid receiving exorbitant fees from the international Duo authentication calls (The Duo call should only take less than a minute, minimizing international call charges).

See also

YubiKey Request Form

Duo in China

IS&T strongly recommends using a hardware token, such as a Yubikey or D100 while traveling in China. Push notifications purportedly work in mainland China, but phone calls are unreliable, and SMS generally gets blocked. If you are planning a trip to China, we encourage you to request a hardware token from IS&T by emailing servicedesk@mit.edu.