I have an airbook with Yosemite 10.10 . Sometimes I run paralels on it. Not sure if it's related but today I was using a windows program and may have shut down without closing out of paralels. In any event, now nothing is showing up on my desktop. I have tried verifying and repairing disk permissions in disk utility. I have tried multiple reboots and I have tried a safe reboot. Still nothing. Any ideas?