I've got a MBA Mid 2013 and since installing Yosemite, I've had 3-4 sleep wake failures. Generally I'll close the lid, head home and either when I open the laptop at home or back at work the next morning I get message (not sure of exact text) "Your computer failed to wake properly and has restarted". It didn't happen with Mavericks nor ML before that.
2 Times it stated the process was Activity Monitor and this most recent time it was airportd.
I don't really lose anything since all my apps open pretty much where they left off it's just a big annoying.
Any ideas?
Best Answer
I have had this happen a few times myself. If I was to guess, at the time you closed you lid on your computer you had the power supply hookup and running. After the lid was closed you removed the power plug. Later you open the lid, without the power plug and it was a blank screen. If this is your case, you have two options,
I have found if I give my Mac a few seconds after closing the lid, before removing the power, it will not freeze later when I open the lid.
Still not sure of the problem, just a work around that I found after a little time with this type of problem.