HI, i am having to re-fromat my NEW Samsung M3 usb 3.0 1tb external HD for the 3rd time in 3 months. I use it with Time machine. A while back i spent 1 hour on the phone with a senior apple care person. He recommended the longer erase, its doing it now so i cant tell you the name of it, the one that writes a zero over all of the HD's memory. It takes a few hours. I did this, and after 1 month time machine doesn't work again. So, i am reformatting again. I work professionally with my mac and when Time machine works, its fantastic. BUT, this is now unacceptable. I am reformatting one more time. If it fails again, i will not use Time machine again. So, Whats the problem? 1. Is it Mountain lion? 2. The new Samsung M3 usb 3.0 drive that is getting great reviews around the web? 3. Maybe Apple will come out with a fix for Time machine? 4. USB 3.0? Our new mac's are the first generation with USB 3.0 could there be an issue with the computer? Getting close to going back to regular back-ups. I know there are a lot of people that don't have problems with Time machine, but there are a lot of people that do. Cheers.