Thanks so much, David.

> At a guess, you are using git master of the emacs client (perhaps via
> melpa, or via some arch git snapshot package), and a released version of
> the notmuch binary.

I am using MELPA -- does this mean I should be using git to get the
binary?

> What is the output of M-x notmuch-hello-versions <return>

notmuch version 0.24.2

---
dwrz|朱为文 

On 2017-07-10 18:14, David Bremner wrote:

> david wen riccardi-zhu <dwrz@dwrz.net> writes:
> 
>> I'm getting this error in Emacs after upgrading packages:
>> 
>> notmuch-logged-error: notmuch CLI version mismatch Emacs requested 
>> a newer output format than supported by the notmuch CLI.  You may 
>> need to restart Emacs or upgrade your notmuch package.
> 
> At a guess, you are using git master of the emacs client (perhaps via
> melpa, or via some arch git snapshot package), and a released version of
> the notmuch binary. 
> 
>> The message appears whenever I try to open an email. 
>> 
>> Emacs is 25.2.1, notmuch is 0.24.2. I'm on Arch Linux x86_64.
> 
> What is the output of M-x notmuch-hello-versions <return>
> 
>> Am I getting this error because Arch needs to update to 0.24.2-2? 
>> Should I switch to git?
> 
> 0.24.2-2 is not an upstream version of notmuch; there is a Debian
> version like that; perhaps arch has a similar versioning scheme. 
> 
>> It would also be nice if this error didn't prevent accessing 
>> messages. : )
> 
> In general this message indicates your emacs lisp components and your
> notmuch binary have drifted dangerously far apart in versions, and you
> should really fix that problem. You can still use the command line
> "notmuch search" and "notmuch show" commands for access to your mail in
> the meantime.
> 
> d