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Just updated from 12.10. Ubuntu cannot shutdown properly, it hangs at the purple ubuntu loading screen with dots animation still moving. It hanged about half an hour. I hold the power button to shut it down.

I happened on every boot. Please help. This is all that I know.

1/5/2013 - 6:59 I tried sudo service lightdm restart code, and returns in console (black screen):

Asking for cache data failed
Assuming drive cache: write through

then after a half screen of attempts, the screen black out (screen saving).

I pressed the power button and another shutdown procedure began.


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I also have this problem. It is solved when I take out the battery from my laptop and then shut down with the power button. Then try to boot and restart, after that the battery can be reinserted. – user154288 May 1 '13 at 2:10
Possible duplicate of this or this. – AliNa May 1 '13 at 4:04
not a duplication since there is no freeze or blank screen – Daniel Cheung May 1 '13 at 10:48

I also face the same problem frequently! I installed a new version of ubuntu13.04 64bit.

Also, when starting the ubuntu13.04, I have to run two times of this command!

sudo service lightdm restart

It seems that some driver or software problem makes it happen.

share|improve this answer
I did it, says in console Asking for cache data fail, Assuming drive cache: WRITE THROUGH – Daniel Cheung May 1 '13 at 10:59

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