One of the first frustrations I had when learning SharePoint was wrapping my head around content types. A seemingly simple thing such as going to the MS Project Tracking template and adding a new column to the project list should mean that from now on, when I add or edit my list, I should see my newly created column just waiting to be filled, right? Wrong!
The reason is this; this template uses a Content Type for the project list and if you ever run into an issue where a column you created is not showing up on the add new or edit page or is not an option for a filter or content query part, the most likely reason is that you are working on a list that is using a content type but the option of “Allow management of content types” is set to “No”.
Go to the list settings – under the heading “General Settings” select Advanced Settings.
The first option is to “Allow management of content types”, set this to yes.
Now when you create a column, a new option will appear: Add to all content types. If this is checked, the column will now show up whenever you go to edit or a add a list item.
What if you have already added a bunch of columns? How can you now have them show up as options when adding and editing list items?
Now when you go to list settings you will notice a new heading above columns for Content Types.
Simply click on the name of the content type (in this case Project) and then on Add from existing site columns, this will allow you to add previously created columns to the lists Content Type.
Hope this helps anyone struggling with this issue. Just to know Content Types are very useful and there is a reason for not adding columns by default to your lists. Even though now it seems a bit awkward an unintuitive.