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ADD - This will format the hard drive (formatting deletes all content present on the hard drive) and expand your MMS's storage capacity. Content needs to be transferred through the Autonomic Sync Tool for it to be stored on the external hard drive.
MOUNT - This will not format your hard drive and will expand your MMS's storage capacity. Any content on the drive will become available after a scanning period. Additional content must be manually copied to the Mounted folder on the Music share of the MMS.
COPY - This will copy all the content from the external hard drive to the MMS's internal and will not expand your MMS's storage capacity
NOTE: For an optimal user experience, we recommend no more than 40k total tracks across all storage media.