You are using the Campaign File Format functionality for your customer campaigns. For the address, you are using a postbox and you would like to use this field in the campaign file format.
Reproducing the Issue
1. Go to the Customer workcenter.
2. Go to the Accounts view.
3. Open any Account
4. Click Edit and note the postbox field is visible and filled with a value.
5. Go to the Sales Campaign workcenter.
6. Go to the Campaign File Format view.
7. Open any Campaign File Format.
Result: The field Postbox is not in the list to be selected.
This is the currently expected system behaviour.
We have added this requirement to the development backlog and it is being considered for a future release.
KBA , LOD-LE-MKT , Marketing , Product Enhancement