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These files are usually set to “hidden,” which means they are invisible in File Explorer (Windows) and Finder (macOS). However, the automatic deletion event that should remove the file when you close the Office file doesn’t always happen. Therefore, an orphaned file remains. This file is no longer connected to the source file, and it will sit there forever. This usually isn’t an issue due to the extremely small file size of the lock file, and they’re “hidden” which means they are never seen by the user.
However now that users are data is being migrated to SharePoint, these files are becoming visible. The data migration tool used by ITS moves these lock files as if they were any other file. None of the files migrated into SharePoint will be set to “hidden,” and all the previously hidden files are no visible to all users.
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