"Applications" , "Places" and "System" have vanished from my taskbar!

Asked by John Ross Peel on 2011-08-12

Making light use of my computer, just on the internet, and the screen shuddered, for want of a better description, the mouse and keyboard stopped working. After around 1 to 1.1/2 minutes things returned to normal, except that on the Task-bar "Applications" "Places" and "System" have disappeared!
I've gone through "System Settings" but could not find anything relevant. When I click on "Help" I get the message:

Unknown Error
The file ‘/usr/share/gnome/help/user-guide/en_GB/user-guide.xml’ could not be parsed because one or more of its included files is not a well-formed XML document.

So, I'm lost! Please help.
                                                                                          Regards, John

Furthur information, which may or may not be relevant. Using "System Monitor" I have found Firefox-bin on occasions is ramping up one of my cores ( AMD Athlone IIX2 250) to 100 percent and everything drops into crawler gear.

Question information

Language:
English Edit question
Status:
Solved
For:
Ubuntu gnome-panel Edit question
Assignee:
No assignee Edit question
Solved by:
actionparsnip
Solved:
2011-08-12
Last query:
2011-08-12
Last reply:
2011-08-12

Can you give the output of:
file /usr/share/gnome/help/user-guide/en_GB/user-guide.xml

You can reset your panels with:
gconftool --recursive-unset /apps/panel && killall gnome-panel

John Ross Peel (johnrpeel) said : #2

Thank you, Andrew,
                                   For both your swift reply and your help. I have my task-bar back and now know what to do in future. My "Shut-down" button used to go walk-about and I had a big red "off" button on the task-bar as stand-by, so that is a second problem solved.
                                  To-night I've been to places in my computer which I did not know existed! I am a recent migrant from an OS originating in Redmond, California, and am still in the primary class-room when it comes to Linux!
Across the top of the page user-guide.xml is a message,

"This XML file does not appear to have any style information associated with it. The document tree is shown below."

and the document tree reads:

!-- -*- indent-tabs-mode: nil -*- --><?db.chunk.max_depth 3?><book id="index" lang="en_GB"><title>Desktop User Guide</title><bookinfo><abstract role="description"><para>The GNOME User Guide is a collection of documentation which details general use of the GNOME Desktop environment. Topics covered include sessions, panels, menus, file management, and preferences.</para></abstract><copyright><year>2005</year><holder>Shaun McCance</holder></copyright><copyright><year>2004</year><holder>Sun Microsystems</holder></copyright><copyright><year>2003</year><holder>Sun Microsystems</holder></copyright><!-- translators: uncomment this:
    <copyright>
      <year>2002</year>
      <holder>ME-THE-TRANSLATOR (Latin translation)</holder>
    </copyright>
    --><publisher role="maintainer"><publishername>GNOME Documentation Project</publishername></publisher><legalnotice id="legalnotice"><para>Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License (GFDL), Version 1.1 or any later version published by the Free Software Foundation with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. You can find a copy of the GFDL at this <ulink type="help" url="ghelp:fdl">link</ulink> or in the file COPYING-DOCS distributed with this manual.</para><para>This manual is part of a collection of GNOME manuals distributed under the GFDL. If you want to distribute this manual separately from the collection, you can do so by adding a copy of the license to the manual, as described in section 6 of the license.</para><para>Many of the names used by companies to distinguish their products and services are claimed as trademarks. Where those names appear in any GNOME documentation, and the members of the GNOME Documentation Project are made aware of those trademarks, then the names are in capital letters or initial capital letters.</para><para>DOCUMENT AND MODIFIED VERSIONS OF THE DOCUMENT ARE PROVIDED UNDER THE TERMS OF THE GNU FREE DOCUMENTATION LICENSE WITH THE FURTHER UNDERSTANDING THAT: <orderedlist><listitem><para>DOCUMENT IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION, WARRANTIES THAT THE DOCUMENT OR MODIFIED VERSION OF THE DOCUMENT IS FREE OF DEFECTS MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE OR NON-INFRINGING. THE ENTIRE RISK AS TO THE QUALITY, ACCURACY, AND PERFORMANCE OF THE DOCUMENT OR MODIFIED VERSION OF THE DOCUMENT IS WITH YOU. SHOULD ANY DOCUMENT OR MODIFIED VERSION PROVE DEFECTIVE IN ANY RESPECT, YOU (NOT THE INITIAL WRITER, AUTHOR OR ANY CONTRIBUTOR) ASSUME THE COST OF ANY NECESSARY SERVICING, REPAIR OR CORRECTION. THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS LICENSE. NO USE OF ANY DOCUMENT OR MODIFIED VERSION OF THE DOCUMENT IS AUTHORISED HEREUNDER EXCEPT UNDER THIS DISCLAIMER; AND</para></listitem><listitem><para>UNDER NO CIRCUMSTANCES AND UNDER NO LEGAL THEORY, WHETHER IN TORT (INCLUDING NEGLIGENCE), CONTRACT, OR OTHERWISE, SHALL THE AUTHOR, INITIAL WRITER, ANY CONTRIBUTOR, OR ANY DISTRIBUTOR OF THE DOCUMENT OR MODIFIED VERSION OF THE DOCUMENT, OR ANY SUPPLIER OF ANY OF SUCH PARTIES, BE LIABLE TO ANY PERSON FOR ANY DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES OF ANY CHARACTER INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS OF GOODWILL, WORK STOPPAGE, COMPUTER FAILURE OR MALFUNCTION, OR ANY AND ALL OTHER DAMAGES OR LOSSES ARISING OUT OF OR RELATING TO USE OF THE DOCUMENT AND MODIFIED VERSIONS OF THE DOCUMENT, EVEN IF SUCH PARTY SHALL HAVE BEEN INFORMED OF THE POSSIBILITY OF SUCH DAMAGES.</para></listitem></orderedlist></para></legalnotice><authorgroup><author><firstname>Sun</firstname><surname>GNOME Documentation Team</surname><affiliation><orgname>Sun Microsystems</orgname></affiliation></author><author><firstname>Shaun</firstname><surname>McCance</surname><affiliation><orgname>GNOME Documentation Project</orgname></affiliation><email><email address hidden></email></author><author><surname>Karderio</surname><affiliation><orgname>GNOME Documentation Project</orgname></affiliation><email>karderio at gmail dot com</email></author><author><firstname>Joachim</firstname><surname>Noreiko</surname><affiliation><orgname>GNOME Documentation Project</orgname></affiliation><email>jnoreiko at yahoo dot com</email></author><author><firstname>Daniel</firstname><surname>Espinosa Ortiz</surname><affiliation><orgname>GNOME Documentation Project</orgname></affiliation><email>esodan at gmail dot com</email></author><author><firstname>Brent</firstname><surname>Smith</surname><affiliation><orgname>GNOME Documentation Project</orgname></affiliation><email>gnome at nextreality dot net</email></author><author><firstname>Tim</firstname><surname>Littlemore</surname><affiliation><orgname>GNOME Documentation Project</orgname></affiliation><email>tim at tjl2 dot com</email></author><author><firstname>John</firstname><surname>Stowers</surname><affiliation><orgname>GNOME Documentation Project</orgname></affiliation><email>john dot stowers at gmail dot com</email></author><author><firstname>Nigel</firstname><surname>Tao</surname><affiliation><orgname>GNOME Documentation Project</orgname></affiliation><email>nigel dot tao at myrealbox dot com</email></author><author><firstname>Matthew</firstname><surname>East</surname><affiliation><orgname>Ubuntu Documentation Project</orgname></affiliation><email>mdke at ubuntu dot com</email></author><author><firstname>Carlos</firstname><surname>Garnacho Parro</surname><affiliation><orgname>GNOME Project</orgname></affiliation><email><email address hidden></email></author></authorgroup><releaseinfo revision="2.26" role="review">
     </releaseinfo><revhistory><revision><revnumber>2.14</revnumber><date>2006-02-03</date><revdescription><para role="author">Karderio</para><para role="publisher">GNOME Documentation Project</para></revdescription></revision><revision><revnumber>2.10</revnumber><date>2005-03-08</date><revdescription><para role="author">Shaun McCance</para><para role="publisher">GNOME Documentation Project</para></revdescription></revision><revision><revnumber>GNOME 2.8 Desktop User Guide V2.8</revnumber><date>September 2004</date><revdescription><para role="publisher">GNOME Documentation Project</para></revdescription></revision><revision><revnumber>GNOME 2.4 Desktop User Guide V2.7</revnumber><date>September 2003</date><revdescription><para role="author">Sun Microsystems</para><para role="publisher">GNOME Documentation Project</para></revdescription></revision><revision><revnumber>GNOME 2.4 Desktop User Guide V2.6</revnumber><date>August 2003</date><revdescription><para role="author">Sun Microsystems</para><para role="publisher">GNOME Documentation Project</para></revdescription></revision><revision><revnumber>GNOME 2.2.1 Desktop User Guide V2.5</revnumber><date>March 2003</date><revdescription><para role="author">Sun Microsystems</para><para role="publisher">GNOME Documentation Project</para></revdescription></revision><revision><revnumber>GNOME 2.2 Desktop User Guide V2.4</revnumber><date>January 2003</date><revdescription><para role="author">Sun Microsystems</para><para role="publisher">GNOME Documentation Project</para></revdescription></revision><revision><revnumber>GNOME 2.0 Desktop User Guide V2.3</revnumber><date>October 2002</date><revdescription><para role="author">Sun Microsystems</para><para role="publisher">GNOME Documentation Project</para></revdescription></revision><revision><revnumber>GNOME 2.0 Desktop User Guide V2.2</revnumber><date>August 2002</date><revdescription><para role="author">Sun Microsystems</para><para role="publisher">GNOME Documentation Project</para></revdescription></revision><revision><revnumber>GNOME 2.0 Desktop User Guide V2.1</revnumber><date>August 2002</date><revdescription><para role="author">Sun Microsystems</para><para role="publisher">GNOME Documentation Project</para></revdescription></revision><revision><revnumber>GNOME 2.0 Desktop User Guide V1.0</revnumber><date>May 2002</date><revdescription><para role="author">Sun Microsystems</para><para role="publisher">GNOME Documentation Project</para></revdescription></revision></revhistory><releaseinfo>This manual describes version 2.14 of the GNOME desktop.</releaseinfo><legalnotice><title>Feedback</title><para>To report a bug or make a suggestion regarding the GNOME desktop or this manual, follow the directions in the <link linkend="feedback">GNOME Feedback Page</link>.</para></legalnotice></bookinfo><include href="gosbasic.xml"/><!-- Basic skills --><include href="gosoverview.xml"/><!-- Overview--><include href="gosstartsession.xml"/><!-- Sessions --><include href="gospanel.xml"/><!-- Panels --><include href="goseditmainmenu.xml"/><!-- Menus --><include href="gosnautilus.xml"/><!-- Nautilus --><include href="gostools.xml"/><!-- Tools & utilities --><include href="goscustdesk.xml"/><!-- Preferences --><include href="glossary.xml"/><!-- Glossary --><include href="gosfeedback.xml"/><!-- Feedback --></book>

I do hope the problem lies in the header to the page, the rest makes no sense to me. If you can get the Help pages working hopefully I won't have to bother you again, at least with the mundane problems.
Thank you again for all your help and enjoy your week-end. John