Mac cannot log on after upgrading Yosemite

Mac upgrade Yosemite After unable to log on to the issue today whim ready to play the latest Apple system 10.10, code is Yosemite. Went to the official website to apply for beta test eligibility, and then in the App Store downloaded a night to get the Yosemite Beta version number.

The upgrade installation process was smooth. But the pit dad is my restart after unexpectedly log on, has been the login page chrysanthemum in that turn ah turn, very long have not entered the system.

At that time to kneel. I haven't backed up the information. Fortunately there is a strong Google. Finally found a solution, a false alarm. This login question is generally reflected on the Internet may be a third-party input method or cleanup software such as CCleaner caused by problems. It happens that I have both of these software installed. And I cleaned up the system garbage once after the upgrade (some key files may have been cleared out).

As a result, on the internet to find a fast one hours, and finally a way to succeed, thanks to Macbookpro Bar Jackatcl friends, here I put the solution is also affixed to the hope that the upgrade of the system of friends to help.
The solutions are as follows: 1. Press and hold the Power key to force the shutdown, then reboot, and when the boot sound is heard, press Command+s to enter single user mode.

2. Input command mount disk writable

MOUNT-UW/

3. Enter the following command to delete the file

rm/var/db/. Applesetupdone

4. Enter the command to restart

Reboot

5. After the system restarts, it will go to the Create New User Wizard, under Simple configuration. Since this only requires the creation of a temporary user, I created a user named Test.

6. After using the test user to enter the system, download Sogou Pinyin Input Method DMG installation package. Open the DMG. Then uninstall Sogou Input method. 7. Log off the user after uninstallation. Then go to your previous account. You can then delete the test user.

Mac cannot log on after upgrading Yosemite