How to import large amount of mailboxes to a collection (4241551)

Preparing the CSV File for Import

To import accounts into a collection, prepare a comma-separated values (CSV) file containing data of discovered source accounts. The file can include accounts that have not been discovered, but these accounts will not be added to the collection.

One of the columns must contain user principal names (UPNs). Examples of columns that can be included:

• userPrincipalName
  Example@tenant.onmicrosoft.com

• email
  Example@testdomain.com

• objectID
  d6801a8b-5cb1-48f4-9757-4465564c5c63

Notes:

• The mapping file cannot be used directly as the fill file but can be modified by removing the target column.

• The CSV can contain one or more columns; there are no special requirements for header names.

• One column must contain case-insensitive UPN data for matching.

• File names with non-ASCII characters are not supported.

• Objects that do not exist in the source or target tenants, or source accounts not enumerated during Discovery, are ignored without producing an event.

Creating and Populating a New Collection

1. On the Dashboard, click New Collection.

2. Enter a descriptive name for the collection and click Save to add it to the project.

3. Locate the new collection in the list and click it.

4. Click Fill from File.

5. Choose the account list type that matches your CSV file: UPNs, ObjectIds, or Emails.

6. Browse to your CSV file, select it, and click Populate.