The process of importing information into a directory service. The information to be imported must be in a format that the importing system can understand, usually a delimited text file such as a .csv file.
Microsoft Exchange Server allows recipient information to be imported into its directory database and allows recipients exported from other mail systems to be imported into Exchange.
For example, you can use the Exchange Migration Wizard to extract mailbox information from a foreign mail system into a .csv file.
You can then import this information into a spreadsheet program such as Microsoft Excel, modify it as needed, and import it into Exchange to create new mailboxes in your organization for users of the foreign mail system who are migrating to Exchange.