Poco User Interface FAQ - Tailoring the message index

Q: Is there a way to display the CC: (or another header field) in the mailbox index?
Yes there is, proceed as follows:
  1. Open the "Options" window (Shift+F7 or Tools->Options).
  2. Click on "Index Columns" in the left pane of the window.
  3. Press the "Column setup" tab.
  4. Enter the name of the header field (eg: CC:) you want to display in one of the "Custom" fields.
  5. Press the "Column visibility" tab.
  6. Select the custom column you used in step 4 above.
  7. Press "Ok".
  8. Compress the mailboxes. The new column(s) won't be displayed until the mailboxes have been compressed.