Hi Jia,

Please take search through answers.ros.org and if you don't find a similar
problem there reask your question there. There are some known issues with
installing on 14.04.2 such as:
http://answers.ros.org/question/203610/ubuntu-14042-unmet-dependencies/
Your error looks slightly different. If you ask your question again please
also mention your architecture.

We try to keep the mailing list focused on community discussions and
announcements. http://wiki.ros.org/Support

Tully

On Fri, Mar 13, 2015 at 4:30 AM, JIA Pei via ros-users <
ros-users@lists.ros.org> wrote:

>
> Hi, all:
>
> I'm using Ubuntu 14.04:
>
> :/$ lsb_release -a
> No LSB modules are available.
> Distributor ID: Ubuntu
> Description:    Ubuntu 14.04.2 LTS
> Release:        14.04
> Codename:       trusty
>
>
> Strictly followed http://wiki.ros.org/indigo/Installation/Ubuntu, but
> failed to install it. Does anybody know why and how to have ROS
> successfully installed?
>
> .....$ sudo apt-get install ros-indigo-desktop-full
> Reading package lists... Done
> Building dependency tree
> Reading state information... Done
> Some packages could not be installed. This may mean that you have
> requested an impossible situation or if you are using the unstable
> distribution that some required packages have not yet been created
> or been moved out of Incoming.
> The following information may help to resolve the situation:
>
> The following packages have unmet dependencies:
>  ros-indigo-desktop-full : Depends: ros-indigo-desktop but it is not going
> to be installed
>                            Depends: ros-indigo-perception but it is not
> going to be installed
>                            Depends: ros-indigo-simulators but it is not
> going to be installed
> E: Unable to correct problems, you have held broken packages.
>
>
>
> Cheers
>
> --
>
> Pei JIA, Ph.D.
>
> Email: jp4work@gmail.com
> cell in Canada:    +1 778-863-5816
> cell in China: +86 186-8244-3503
>
> Welcome to Vision Open
> http://www.visionopen.com
>
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