[[!img notmuch-logo.png alt="Notmuch logo" class="left"]]
# Frequently Asked Questions

[[!toc levels=2]]

## How come this query matches mails in folder:2013? `notmuch search --output=files folder:inbox`

You have duplicates of a message (or messages) in both folders.

Notmuch searches are message based. Multiple files may be associated
with the same message (i.e. the files have identical Message-ID). A
`folder:` search will match the folder of any of the files. The
`--output=files` option outputs all the files of all matching messages.

## Shouldn't notmuch support inline PGP?

[Why it might not be a good idea](https://dkg.fifthhorseman.net/notes/inline-pgp-harmful/)

## How do I delete messages

See [[excluding]].

## How do I configure the citation line when replying in Emacs?

        (setq message-citation-line-format "On %a, %d %b %Y, %f wrote:")
        (setq message-citation-line-function 'message-insert-formatted-citation-line)

See help for `message-citation-line-format` for details.