1 # Frequently Asked Questions
5 ## How come this query matches mails in folder:2013? `notmuch search --output=files folder:inbox`
7 You have duplicates of the message in both folders.
9 Notmuch searches are message based. Multiple files may be associated
10 with the same message (i.e. the files have identical Message-ID). A
11 folder: search will match the folder of any of the files. The
12 --output=files option outputs all the files of all matching messages.