Open this link:- webmail.spectrum.net in your web browser.
After that, login your Roadrunner email account with the help of email address and password.
Open the option of setting bar, then open the section of people.
In the section of people , enter the button of Add person.
Then, Follow all the necessary instructions which is required on this page
At last, enter the button of save.
Follow above mentioned steps to add Username in Roadrunner email login account.
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