You can edit the settings for custom columns, whether they are currently active or not.
1. Select More in the project view and choose Customise project.
The Customise project dialog opens.
2. Select the Column management tab.
3. Select any custom column in either the Available columns or Activated columns list.
4. Select Edit.
The Edit custom column dialog opens.
5. Make the required changes. See Adding custom project columns for information on the available options.
6. Select OK to save.