Can not permanently delete emails (or folder) from recovered folde

I have two recovered folders (on my hard drive or in my personal folders).

When I try to delete from them I can not and get the error message "The
messaging interface has returned an unknown error. If the problem persists,
restart Outlook."

1) Restarting does nothing to solve the problem.
2) An empty deleted folder does nothing to solve the problem.
3) Moving the folders to the deleted folder does nothing to solve the
problem because I can not delete them from the deleted folder. (Individual
emails can not be moved to the deleted folder, only the entire folder.)
3) Running scanpst.exe against the pst file does nothing to solve the
problem.

a) I can deleted all attachments and then "save changes" -- this has allowed
me to reduce the size of the folders.

QUESTION: How can I get rid of these emails / folders?

Thanks!