I should note, this user had existed in the past, left, and then came back to be reactivated.
I inherited this Redmine system in the interim, so I don't know all of tis details (read: quirks)
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When attempting to create the user name.last@student.email.edu, Redmine fails the user add saying The email is already in use.
However a search of Redmine users shows no such user, and can find no such email.
When searching in Redmine for both MY username and my email - both come up, so I think I'm doing the search correctly.
Redmine users are validated against an Samba Active Directory domain (not locally).
The user account seems to be fine in Samba Active Directory.
One user can have multiple e-mail addresses, best way to resolve that situation is to either seek for that user via ruby console or with some SQL database query tool.
Console approach:
To activate ruby console, just on your Redmine server, navigate via terminal or cmd on windows to Redmine install folder and type rails console, you might need to add RAILS_ENV=production if required.
EmailAddress.find_by(address: "my@address.com")
Replace my@address.com with address you are looking for, or
That would return result like:
#<EmailAddress id: 3, user_id: 1, address: "my@address.com"...
Than in following query, you can get exact user id, by using user_id from previous query:
User.find_by(id:id_from_previous_query)
Just replace id_from_previous_query, with proper id, retruned in previous query.
Database approach:
E-mail addresses are located in email_addresses database table.
Below is sql code that you can run if you installed Redmine with MySql/MariaDb, just replace %search% with email or part of email that you are searching for
select login,firstname,lastname,address from users left join email_addresses on users.id=email_addresses.user_id where email_addresses.address like '%search%'
I have also created feature proposal, based upon your inquiry here: https://www.redmine.org/issues/31043