Error occurred in deployment step ‘Activate Features’: The ContentType with id defined in feature

1. Include Inherits="True" and take off Overwrite="True" for Content Type
2. For Fields, Include Overwrite="True"

Sometimes: stop-process -processname vssphost4 -force 

Useful Links:

http://tchmiel.wordpress.com/2010/08/09/activate-feature-error-custom-content-types-when-debugging-from-visual-studio-2010/

http://social.technet.microsoft.com/Forums/en-US/sharepoint2010programming/thread/fdaed928-21ed-414d-ac2a-06f1e068bcd1/

http://blogit.create.pt/blogs/andrevala/archive/2008/03/26/SharePoint-2007-Deployment_3A00_-Site-Column-Features.aspx