NewInstance

Yesterday I noticed that when I close the lid of my MacBook Pro the light in front of the case was not indicating that the computer was going to sleep normally. Still the fans were running and when I opened the lid, I saw that it was not resuming from sleep properly, presenting a strange behavior: it asks for a password for a second or so, then the screen goes black again, and I need to turn it on manually pressing the light buttons (fn+F1/F2) then the screen appears again.

I debugged the problem and I discovered the cause.

The cause is that I enabled “Internet Sharing” from the “Sharing” item in the “System Preferences”. Basically I am sharing the WIFI internet to set of devices connected to the Ethernet.
If the WIFI is enabled (and connected) and the Internet Sharing is enabled, my MacBook hangs while doing the sleep process.

After resetting the SMC and trying several times to close all possible apps which may interfere, I finally found that the Internet Sharing is affecting this behavior.
Another workaround I found is to disable the WIFI. In this way the “Internet Sharing” is also disabled and the problem doesn’t happen anymore.

I reported the bug to Apple, and I hope they will have a look and try to solve it. To me, it is obviously a BUG in the Internet Sharing feature, which by the way it’s superb.