Cortex uses a single sign on (SSO) system that links the users ACR credentials (the username and password used for and their Cortex account.  The second Cortexlogin box as seen below will display when the user has never accessed Cortex before and their ACR account is not yet linked to their Cortex account.  To link the accounts, enter the Cortex username and password given by your User Administrator or contact Cortex support for additional assistance.