Several devices for Two Way Authentication

To add more than one device

Have two or more devices ready with the two way aithentication app
like Google Authenticator or Authy (normally they need be of the same
type like iOS or Android or Windows Phone or Blackberry - you can't
have different)

Activate the two way authentication scenario and scan / write the
code on both devices before confirmation of the code

IF you ALREADY have the two way authentication activate on one
device. Then logon to the service and go to the activation of the
two way authentication.

On the one device - delete the account for the two way authentication
and restart the process from the beginning of this page. DO NOT log
out until everything is in the clear

In som scenarios you must disable the two way authentication and
then reenable it on the specific service

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