Problem in Login for Precise Ubuntu 12.04 (unstable release ) after upgrading system

Use CTRL+ALT+F1 to switch to a console. Login there. If you cant login, type your password in the logon dialog just to make sure the right characters are appearing and your keyboard isn't broken. Once you have confirmed, logon and then update again. However you should use dist-upgrade not upgrade.

sudo apt-get update
sudo apt-get dist-upgrade

You'll probably get more updates installed. Also worth making sure you have everything that should be installed.

sudo apt-get install ubuntu-desktop^

The caret (^) is important.

Once that's done, reboot and see if you can login.

Thanks for Alan Pope ,My problem is solved.

On Tue, Feb 14, 2012 at 5:10 PM, Alan Pope <
<email address hidden>> wrote:

> Your question #187642 on Ubuntu changed:
> https://answers.launchpad.net/ubuntu/+question/187642
>
> Status: Open => Answered
>
> Alan Pope proposed the following answer:
> Use CTRL+ALT+F1 to switch to a console. Login there. If you cant login,
> type your password in the logon dialog just to make sure the right
> characters are appearing and your keyboard isn't broken. Once you have
> confirmed, logon and then update again. However you should use dist-
> upgrade not upgrade.
>
> sudo apt-get update
> sudo apt-get dist-upgrade
>
> You'll probably get more updates installed. Also worth making sure you
> have everything that should be installed.
>
> sudo apt-get install ubuntu-desktop^
>
> The caret (^) is important.
>
> Once that's done, reboot and see if you can login.
>
> --
> If this answers your question, please go to the following page to let us
> know that it is solved:
> https://answers.launchpad.net/ubuntu/+question/187642/+confirm?answer_id=0
>
> If you still need help, you can reply to this email or go to the
> following page to enter your feedback:
> https://answers.launchpad.net/ubuntu/+question/187642
>
> You received this question notification because you asked the question.
>

hi