There are many tools available in the market to
migrate GroupWise to Office 365 cloud. If you are hunting for a safe and secure tool that can perform this task without data alteration and loss, you can look up Weeom. Weeom GroupWise to Office 365 Migration tool inherits a simple and detailed GUI along with necessary features. A few of its features are Preview, Folder & Mailbox mapping, Filters, etc. Weeom knows that users may require to backup GroupWise data, therefore, also let users back up GroupWise data in EML, MSG, and PST file formats. Moreover, to contain PST within a secure size limit, this tool also facilitates PST split feature.
For more details, visit:
https://www.weeom.com/groupwise-to-office365.php