I have recorded how I upgraded my Mavericks based Mac to Yosemite newest OS which was released not too long ago.
However, right after I upgraded, I found a strange thing happening with my Time Machine.
My Time machine isn’t working anymore. When I plugged in my external hard drive to my Mac, it was detected on Finder, (if not, this link might help) but it was circle-ing all the time, and in my menu bar on the top right, showing “Preparing Backup” or “Backing Up from xx to xx GB”, it takes forever than usual.
