There a simple and efficient method to migrate Kerio to Office 365 account. Try this Kerio to Office 365 Converter that is easy to use and supports transfer of multiple Kerio users to O365 account in bulk. It uses mailbox mapping feature that allows migration of Kerio users to Office 365 users, through admin account, eliminating the need for signing-in each user account individually. You just need to upload the CSV file containing path of your Kerio users and their respective Office 365 users where you want to migrate Kerio data.

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