When Outlook is running in cached Exchange mode, Outlook data is stored in user-specific .OST files. These .OST files must follow the users as they roam from host to host. Windows Search Service indexes locally stored .OST files and creates an index catalog for each user to enable search functionality in Outlook. In non-persistent and load-balanced Remote Desktop Service environments, the index catalog doesn’t roam with user data. As a consequence, the index catalog must be rebuilt every time the user logs in and the Connection Broker send him or her to a new pooled desktop or a different RD Session Host within a Collection. FSLogix’s Office 365 Container was designed to solve this issue by roaming a user’s Outlook data as well as their search index catalog in such a way that it is compatible to the Windows Search Service. The FSLogix O365 Container implementation is based on a file system filter driver that redirects the users’ .OST files to virtual disks attached to the local file system in such a way that makes the VHDs look like local folders. This enables users to use the local Windows Search service in Outlook while they are accessing their emails. But how good is this solution in terms of performance and end user experience? The folks from RDS Gurus have the answer.