virtualbox.org

I'm running OS 10.9.1 (Mavericks) with VB 4.3.6 and have discovered that when my display is either sleeping or the screensaver is on I lose network access to my Windows guest machine. I can verify this by putting my display to sleep and running a ping from another system and after about 30 seconds the pings no longer reply. I cannot access the computer remotely at all. Once I wake up the screen pings reply and I can access the machine remotely. I have seen the issue with both Windows 7 and Windows 8 guests. The guests are configured for bridged networking but I believe the same issue is seen if I switch to NAT. Has anyone seen anything similar to this?

Have you checked the Energy Saver settings to make sure that you're not putting the hard drive(s) to sleep also?

Yes, the drives are not set to go to sleep.

In case anyone else has this problem and stumbles across this post, the issue was being caused by the App Nap feature:
http://reviews.cnet.com/8301-13727_7-57 ... mavericks/