Dreaded circle with slash through it

Maybe reinstalling Lion right on top would fix it without reformatting the drive?

 

Same issue with Windows might apply here; the installation on the previous drive is specific to your old MacBook's hardware so the drastic hardware change detected by trying to boot off of it in the new MacBook is failing.

Go into the Recovery Console and reinstall OS X over the hybrid drive's installation and you should be good to go.

 

bbnj62 I think Geo411m is correct.

I just bought a new Mac and when I tried to boot off my 3rd party SSD I got the same circle with the slash that you are talking about. I did boot in safe mode and it does seem that it is an issue with the build version of the OS and most likely the logic board on the new machine.

Im,as I write this, reformatting the drive in a HDD enclosure and hopefully this resolves the issue. You'll need to do this with the new macs hard drive installed on the new Mac.

I'll let you know if this resolves the issue and make sure you back up!!!!!! I'll reply with step-by-step instructions once I find a solution.

 

Try holding down Command R when booting and see if it manages to load the recovery partition (or prompts for a WiFi network to download an updated one). If so, it should be straightforward to overwrite Lion with a working version. Hope you have a backup of that disk in case something goes wrong though.

 

Noticed the same when I pulled the SSD from my old 09 MBP. I think the OS on your external doesn't have some needed drivers or whatnot for the new Ivy Bridge architecture.