I have an external USB hard drive I use for backing up my MacBook (running the latest Lion). FWIW, it's a Western Digital internal 3.5" SATA drive in an Antec HD enclosure. Anyway, of course every so often I have to unplug it so that I can take my MacBook places, so I eject the drive as usual and everything's cool.
But when I plug the drive back in, it doesn't mount. If I plug it in and then power-cycle the drive itself, then it mounts just fine, but due to how my office is laid out, this is inconvenient. And, too, I shouldn't have to power-cycle the drive, right? I should be able just to plug it in and have the MacBook recognize it, no?
So: what's going on and how can I fix it?
Thanks in advance for any and all help.