Browse to portal.office.com:
Enter in your CNETID@uchicago.edu email address and click Next.
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It redirects to the SSO page:
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Enter in your CNET ID and CNET password.
There will be a download/installation option in the top right of the O365 page.
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If you get any errors logging in, please try clearing your cache/cookies in your browser and try again, or call IT Services at 773.702.5800 for further assistance.