Summary
From the inception of Microsoft 365 (then known as Office 365) in 2013, the username used to log into the service has been the same as a user’s primary email address. This username is solely utilized by services that leverage Microsoft 365 for authentication and does not align with the usernames utilized by other cloud services. This mismatch leads to multiple challenges.
Microsoft 365 now supports separating the username from the primary email address. The M365 and Active Directory teams propose to resolve this inconsistency by pivoting to use the Institutional Identifier (IID) for M365/Entra ID authentication while leaving users’ primary email address unchanged. This change will ensure a single, consistent cloud identity regardless of service or authentication method, and permit easier integration between existing and future offerings.
Key Terms
Institutional Identifier (IID) - This is an identifier in the format <eid>@eid.utexas.edu, designed for use with cloud-based services whose usernames are e-mail addresses. (adapted from https://iamservices.utexas.edu/?glossary=iid)
Primary Email Address - This is the Microsoft 365 address that messages a user sends will appear to originate from.
Username - In Microsoft 365, this is the identifier used when logging into the account.
Goals
The project team will consider the project to be complete if, at the conclusion of this project, the following goals have been achieved:
For all active, eligible Microsoft 365 users, usernames are set to IIDs (<EID>@eid.utexas.edu).
The Microsoft 365 and Entra ID platforms are in better alignment with – and can better support – strategic University technology priorities.
Project Timeline and Updates
April 2025
18 April - Change notification sent to Batch 6 pilot participants
18 April - Change applied to Batch 5 pilot participants (163 users)
11 April - Change notification sent to Batch 5 pilot participants
11 April - Change applied to Batch 4 pilot participants (80 users)
9 April - Provided project update to IT Leadership Council (ITLC)
4 April - Change notification sent to Batch 4 pilot participants
4 April - Change applied to Batch 3 pilot participants (35 users)
March 2025
28 March - Change notification sent to Batch 3 pilot participants
18 March - Pilot expansion announced to campus
14 March - Change applied to Batch 2 pilot participants (218 users)
7 March - Change notification sent to Batch 2 pilot participants
February 2025
27 February - Change applied to Batch 1 pilot participants (140 users)
20 February - Change notification sent to Batch 1 pilot participants
18 February - List of initial pilot participants due to project team
6 February - Pilot announced to campus
January 2025
31 January - Final check-in with Microsoft technical resources
14 January - Project Kickoff
Additional Information
This page summarizes the IID in Microsoft 365 project. Check back here for project updates!