I have the same problem. I have a bunch of encrypted text in my notes, working fine on Windows and Android. But I just installed a fresh Evernote on fresh MacBook (OS X 10.9), and when I decrypt the text it is empty. I was careful not to type anything into the empty space, so I still have the content intact when accessing it from Windows/Android. I tried to get to it from the Web interface, but the content is empty as well. I opted into Beta of the new Web UI, so I don't know if the old UI still works with old encrypted notes. I also tried creating a *new* note with encrypted text on the Mac and it worked fine.