Apart from the UPN, you can leave all the other fields blank except the Country or Region, which Office 365 needs to assign licenses as some features are country-dependent. Ideally, the UPN is the same as the email address you want to assign to the new account, and the email address must also be unique. All you really need to populate is the User Name (User Principal Name or UPN), which must be unique. If you’ve done this before, you might already have prepared a file for processing – or if you’re very lucky, someone else has done the work manually or by generating the necessary data from another application, like a HR system. You now have the choice to download a prototype CSV file to populate with details of the accounts you want to create. To begin, head to the Active Users section of the Admin Center and select Add multiple users. Preparing a CSV for Bulk Account Creation

However, there are some issues that need to be taken into account. The idea is to relieve the tedium of creating multiple accounts, a value that anyone who has had to populate a tenant with account information (for real or to build out a test tenant) can easily recognize. Use the data in the CSV file to create accounts.Upload the CSV file to the Admin Center.Populate a CSV file with account details (a limited number of properties are supported).The Office 365 Admin Center and its latest iteration, the preview version of the Microsoft 365 Admin Center (much nicer to use in parts), both offer the option to bulk-create Office 365 accounts. Relieves Some of the Boredom Involved in Adding Users Maybe Roll Your Own Bulk Creation with PowerShell?.Bare-Bones Office 365 Accounts Generated.Preparing a CSV for Bulk Account Creation.Relieves Some of the Boredom Involved in Adding Users.

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