What is the .oldfiles folder in my AFS home directory? Why can't I remove it?
The .oldfiles folder is a read-only backup of your AFS home directory. It is placed in all AFS home directories to provide an easy way for users to restore a previous copy of files modify or deleted within the last 24 hours. It cannot be removed, but also has no impact on your overall AFS quota usage.
For more information, refer to the ITS documentation page: Using AFS File Backup and Restore Services