Duplicate folders for Drafts, Sent, Spam and Trash

[Dave Rado]

I use K-9 Mail as my email client for Gmail. I recently reinstalled it because of some problems I was having (reported in a separate thread) - and now I have duplicate folders for Drafts, Sent, Spam and Trash. For example I have one folder called "Drafts" and one folder called "[Gmail]/Drafts", and so on.

Initially, both sets of duplicate folders displayed exactly the same emails as each other when opened (so for example, the "Drafts" folder and the "[Gmail]/Drafts" folder displayed the same emails as each other).

I then tried going to Account Settings -> Folders, and changing the setting for the Drafts folder from the "Drafts" folder to the  "[Gmail]/Drafts" folder, and so on for the other three. But I still have duplicate folders for all four, but now the folders called "Drafts", "Sent", "Spam" and "Trash" are empty, and the emails are only displayed in the folders prefixed with [Gmail].

How can I get rid of the duplicate folders?

Dave