Redmine

Hi,
We were using bitnami redmine stack 2.6.1.We have now created our own redmine from scratch from ubuntu redmine package and migrated DB from bitnami stack redmine.Now we face the following issues:
If I go to settings page of the project , I get this following error.Kindly help us out.

Started GET "/redmine/projects/test/settings" f
Processing by ProjectsController#settings as HTML
Parameters: {"id"=>"test"}
Current user: redmine (id=1)
Rendered projects/_form.html.erb (13.4ms)
Rendered projects/_edit.html.erb (15.3ms)
Rendered projects/settings/_modules.html.erb (3.4ms)
Rendered projects/settings/_members.html.erb (75.6ms)
Rendered common/_tabs.html.erb (98.5ms)
Rendered projects/settings.html.erb within layouts/base (99.0ms)
Completed 500 Internal Server Error in 112.7ms

ActionView::Template::Error (The single-table inheritance mechanism failed to locate the subclass: 'GroupNonMember'. This error is raised because the column 'type' is reserved for storing the class in case of inheritance. Please rename this column if you didn't intend it to be used for storing the inheritance class or overwrite Principal.inheritance_column to use another column for that information.):
74: </p>
75: <%= javascript_tag "observeSearchfield('principal_search', null, '#{ escape_javascript autocomplete_project_memberships_path(Herve Harster, :format => 'js') }')" >
76: <div id="principals_for_new_member">
77: <= render_principals_for_new_members(Herve Harster) >
78: </div>
79: <p>
80: <= l(:label_role_plural) %>:
app/helpers/members_helper.rb:25:in `render_principals_for_new_members'
app/views/projects/settings/_members.html.erb:77:in `block in app_views_projects_settings_members_html_erb___4106070888830057281_69991626482940'
app/views/projects/settings/_members.html.erb:66:in `_app_views_projects_settings__members_html_erb___4106070888830057281_69991626482940'
app/views/common/_tabs.html.erb:24:in `block in app_views_common_tabs_html_erb__2021980007939450826_56020620'
app/views/common/_tabs.html.erb:23:in `each'
app/views/common/_tabs.html.erb:23:in `_app_views_common__tabs_html_erb__2021980007939450826_56020620'
app/helpers/application_helper.rb:272:in `render_tabs'
app/views/projects/settings.html.erb:3:in `_app_views_projects_settings_html_erb__345123016877819471_55981600'