If you’ve had issues with your Mac hanging after it has been a sleep, and you have an external drive connected to it, join the club. The problem for me was that I had my Energy Saver preferences set to place the external hard drive to sleep whenever possible. I now use a simple workflow that has corrected the problem on my iMac.

I have the checkbox that reads “Put the hard disk(s) to sleep whenever possible” unchecked. I also have the “Computer sleep” settings pointing to “Never”. This way my drive is always available. If I know I’m finished using my iMac and I’m not going to be using it, and I want to change the settings so that it will go to sleep, then I unmount/eject my external hard drive and turn it off. This way my iMac can comfortably go to sleep and wake up without losing the connection to the external drive. After the iMac is awake, I reconnect the external drive and it automatically mounts the drive. I then turn the “Computer sleep” mode to “Never” again.

It is a little bit of a hassle, but since I’ve adopted this workflow with my 1.5 Terra-byte Firewire drive, I’ve had no issues. Do you have any better or different solutions? Post them in the comments.