I upgraded my work iMac to Mavericks and it crashes every time it loads the desktop. It's always within one minute but often within 10 seconds. I reinstalled it twice to no avail. I used every Disk Utility option to check and repair the disk to no avail. I even created a small partition and did a clean install (I did import my settings and content from the old version) and the problem persists. I have no idea what could be the problem. Disk utility days the disk is perfectly fine. Please help!