CCK, or Content Construcion Kit is at the heart of many Drupal 6 sites. If you are migrating, you not only need to migrate the module, but you need to migrate the data as well.
This is a little more complicated than a simple upgrade.
Much of Content Construction Kit (CCK) in Drupal 6 is part of Drupal 7 core fields. Much but not all of CCK functionality is now part of Drupal 7 core. Several features require the installation of new, dedicated 7.x modules.
1. Download CCK and additional modules.
- http://drupal.org/project/references This project maintains the D7 versions of the 'Node reference' and 'User reference' field types, that were part of the CCK Package in D6.
- http://drupal.org/project/field_permissions Content permissions now require the Field Permissions module
- http://drupal.org/project/field_group Field Groups now requires the Field Group module.
- http://www.drupal.org/project/cck The latest CCK Module for 7.x
2. After completing the core upgrade, install CCK for 7.x
Click Install new module, then browse for the module on your computer, and click install.
Repeat this procedure for all four modules.
3. Enable CCK and Content Migrate
Put a check mark next to each one. Then expand the Fields section which will be lower on the page and put a checkmark next to each of those as well.
4. Enable the Fields module.
When you've put check marks in all the boxes scroll to the very bottom of the page and click the Save Configuration button.
To migrate the fields, go to Structure>Migrate fields and click on it. A new page will open with a list of fields to migrate. Click the checkbox next to each one you wish to migrate and click and be sure to save it when you are done.