If you own a Western Digital branded external hard drive you might want to be careful about upgrading to Mavericks. The hard disk manufacturer has emailed customers warning of data loss when upgrading to Mavericks if its Drive Manager, Raid Manager or SmartWare applications are installed.
The email to customers comes after the company support forum exploded with users complaining that they experienced data loss after upgrading to Mavericks with the applications installed. The company says if users uninstall all three pieces of software then they are safe to upgrade to the new OS and will not lose their data. If you’ve already upgraded, you should delete the applications right away to be sure your data is safe.
While the software is being fixed, it has been removed from the Western Digital website.