Event ID - 291

Event Id291
Description"Description 1.
Unable to create Mailbox Username because the required Home-Server attribute was not specified.
Description 2.
Unable to process object <alias name> because the import line must contain the same number of fields as the header line.<number> were expected. <different number> were found."
Event InformationAccording to Microsoft:
This issue can occur because the import file needs the Home-Server column in the header to create a new mailbox. The default mode is update, which creates the object if it does not exist or modifies the object if it does exist.
To resolve this issue, add the Home-Server column to the Header.csv file.
Reference LinksXADM: Event ID 292 When Performing a Directory Import

XADM: Error 291 with Exchange Bulk Import

XADM: Bulk Import/Export FAQ

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