Please help. My Toshiba 750GB External Hard Drive can not be detected by my MacBook Pro. No light. Opened disk utility, but still did not appear. I already did rebooting, reset NVRAM & SMC. I have been using this for backup in my time machine.
Sometimes, often, you have to restart with it plugged in. Also try another port, another cable. Last resort, pull it out and put in another enclosure. What file system are you using?