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Please see the CloudID FAQ.
Can I associate my UT e-mail address (or other e-mail addresses) with my UTBox account?
While your CloudID (your_EID@eid.utexas.edu) is the primary e-mail address on record, your collaborators may not recognize you by this identifier. Fortunately, you can associate multiple e-mail aliases with your account. More information on adding aliases can be found at: https://support.box.com/hc/en-us/articles/200796017-Can-I-add-multiple-email-aliases-to-my-Box-account-.
What happens to my Box account when I leave the university?
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