I downloaded Mavericks on my MacBook Pro that I bought at least in 2011 or 2012. It ran on Snowleopard thus not allowing some web applications to be downloaded. Mavericks allowed these downloads, HOWEVER, I have a Wacom Tablet Intuos 4 that I can't use anymore. I go to System Preferences and click the tablet icon at the bottom. All it tells me is that "Tablet USB was not found when system started. Shut down, check connections and restart. Or reinstall software." I shut down, checked connections, and restarted. It did the same thing. I reinstalled the software and it does the same thing. I can use the tablet and pin like I would use a mouse if I go in and manually speed up the track pad so my pin isn't slow. However, I use my tablet to do graphics and art for a website. In Photoshop CS5 (which still works), my tablet settings will not work. The pressure sensitivity doesn't work. Like I said, all it does is act like a mouse cursor instead of a drawing pin like its purpose is. I backed all my images, which were the only important things to me, (I still have my Photoshop CS5 program disk and my tablet disk) onto my Google Drive. What can I do?