If you’ve memorized the names of the distribution lists you use often, you’ll have to re-memorize the new names.
In Outlook, when you start typing a distribution list in the ‘To’ field, you are offered suggestions of people, mailboxes, and distribution lists that you use frequently. Many of these will no longer work because they’ve been assigned new names.
Here’s an example:
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@RRU-EPMO-Ambassadors will no longer work because that will have been renamed.
You can hit that X to the right to delete the distribution list name from your ‘recently used’ list, if you like. Or wait for it to be replaced with things you use frequently over time.
Notice that RRU Student Services, RRU-Key-Requests, and RRU Computer Accounts don’t have an ‘@' symbol to the left. That’s because these are mailboxes, not distribution lists. These are not changing.