Acid Pro was a DAW software that was previously released by Sony. This was delivered with a version of the ARIA Player and a selection of Garritan Instruments. This product has been discontinued and support no longer exists for this.
If you would like more information about the Garritan line of sample instruments please head to the Garritan home page here.
Currently, the Acid Pro software is now owned and distributed by Magix. Please feel free to contact them directly for more information about this product here Magix Products.