Alaa,
Please open Toolbar.ascx and remove the following code:
<img title="[[UI_MENU_Signout]]" src='<%=ResolveUrl("images/logoff.gif")%>' class="button" onmouseover="this.className='buttonover'"
onmouseout="this.className='button'" onclick="ChatUI_QuitWithConfirm()" />
asp.net Chat http://cutesoft.net/ASP.NET+Chat/default.aspx
Web Messenger: http://cutesoft.net/Web-Messenger/default.aspx
asp.net wysiwyg editor: http://cutesoft.net/ASP.NET+WYSIWYG+Editor/default.aspx
asp wysiwyg html editor: http://cutesoft.net/ASP
asp.net Image Gallery: http://cutesoft.net/ASP.NET+Image+Gallery/default.aspx
Live Support: http://cutesoft.net/live-support/default.aspx