Known issues

Below is a list of known Corso issues and limitations:

Only supports Exchange (email, calendars, contact) and OneDrive (files) M365 data. Additional data types and services will be added in subsequent releases.
Backups of Exchange email may not include changes to the read status of an email if no other changes to the email have been made since the previous backup.
Restores are non-destructive to a dedicated restore folder in the original Exchange mailbox or OneDrive account. Advanced restore options such as in-place restore, or restore to a specific folder or to a different account aren't yet supported.
Restoration of Nested attachments within Exchange Mail or Calendars aren't yet supported.
Folders and Calendars containing zero items or subfolders aren't included in the backup.
Provides no guarantees about whether data moved, added, or deleted in M365 while a backup is being created will be included in the running backup. Future backups run when the data isn't modified will include the data.
OneDrive files ending in .meta or .dirmeta get omitted from Details and Restore commands.
Exchange Calender Event instance exceptions (changes to a single event within a recurring series) aren't included in backup and restore.
Calendar backup and restore is only supported for calendars which belong to user's default calendar group.