04-29-2012, 04:42 PM

I have two external hard drives.

I leave them plugged in much of the time. When I restart the computer, it doesn't "see" them anymore.

The Mac will "see" them if I unplug them and plug them back in.

But it's a pain to have to unplug them and plug them back in every time I restart.

There must be something I can click on -- preferences? system? -- to say:

"Hey, Mac, look around and see if you notice there are two external hard drives plugged into you."

What would that thing be?

Thanks for any help,

Reilly

04-29-2012, 08:39 PM

They should automatically remount whenever you restart the computer. The Mac automatically does exactly the kind of check you describe at startup.

04-29-2012, 10:14 PM

Huh. Well, if it's supposed to do that, it's not doing it.

Any way to make it do that?

Thanks for the reply, buddy.

04-30-2012, 03:21 AM

Are these "self-powered" drives by any chance?

04-30-2012, 12:26 PM

Ah ... yeah, I guess so.

Good call.

So ... what would that mean?

05-01-2012, 06:43 AM

They're not getting enough power at startup to mount. Once the computer is running, they can get enough power from the USB ports to mount.

This is because these sorts of USB drives are intended for temporary use while the computer is on, say for example you want to plug in the drive and move some photos over, then dismount them before you pack up and go. Works PERFECTLY for that sort of thing. But they're not designed for semi-permanent use (ie persistent through restarts).

Two solutions:

1. Plug the drives into a power source (assuming they have a power port and an adapter cord). Then they will mount normally on restart as you're wanting.

2. Get a dual-head USB cord (looks like this):



That gives the drive 2x the 5W it's getting from the one USB port, which should be enough to mount or even boot the machine if there's a system on the external drive on startup. This will work *IF* you're plugging both USB heads into either a) USB ports on your computer, or b) a *powered* USB hub. It won't work at all with an UNpowered USB hub for obvious reasons.

Otherwise, you'll just need to adapt to using them the way they were designed, as drives that are plugged in, used, and dismounted while the computer is already up and running.

05-01-2012, 11:28 PM

Wow, thanks for that. Appreciate the answer, and your time.

I'll try and return them for non-self-powered drives. Otherwise, I'll just plug and unplug them for the rest of my life.