I have used this on a Macintosh for 2 years. It is plugged into my computer, via USB cable, and I have scheduled weekly backups using Apple's "Backup" software, without any problems. I sent one to my Son, who is in Iraq and on a PC, to back up his laptop. The one downside for a laptop is it could drain power since it does not have its own power source. This hard drive lasted 3 months. After 3 months he got an error message. When he came home on leave, he took it to a computer tech who could not recover his pictures and music. Amazon took it back and only refunded me 80% of purchase price and charged me with shipping. I was not pleased, and needless to say my Son was very disappointed that he lost his files.