Before you start migrating, consider the following:
Before starting a migration, bear in mind that time consumed by the migration process depends on size on accounts involved. It is recommended to get the network and all users involved ready for outage of email services and for migration in low-load time. Migration can be also done step by step by smaller groups of users.
Migration requires preparation of a CSV file that would include users and their passwords. This information is crucial for access to the source IMAP server. Make the data in the csv file follow this pattern: user@domain.com;password;Full Name
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