Mail flow will stop working for these public folders after the migration is finalized. Please check whether these are important ...

Mail flow will stop working for these public folders after the migration is finalized. Please check whether these are important folders for your organization.{0}Usually, these mail public folders are legacy system folders created by old versions of Active Directory synchronization scripts or DirSync if your organization has a hybrid Exchange Online deployment. You may run the Sync-MailPublicFolders.ps1 script on your source Exchange server to automatically detect legacy system folders and update Exchange Online to ignore them during migration. You may also run "Set-MailPublicFolder -IgnoreMissingFolderLink:$true" for each AD object that is a legacy system folder and resume the migration. Since legacy system public folders do not need to be mail-enabled on Exchange 2013 or later, it is safe to ignore errors reported while mail-enabling them during migration. If you believe these are not legacy system public folders, please contact customer support. Mail public folders impacted: {1}.