If you participated in an Apple Xsan Seed program, you will need to uninstall Xsan Beta before installing Xsan 1.0. Apple does not support upgrading Xsan Beta to Xsan 1.0.
Uninstalling Xsan Beta will delete Xsan volume(s), so make sure that you back up all your data and test your backups to ensure that you won't lose data. For instructions on how to uninstall Xsan, please see this article. For further instructions on uninstalling Xsan, click here.
Once the Xsan Beta software has been uninstalled, install Xsan 1.0 from the Xsan installation disc. After the installation has completed, you will need to manually recreate all volumes and restore all data to the new volumes.