Hi

>> The code is not of the same standard as mainline code: in particular a
>> lot of the code is written by me and is working but unidiomatic
>> lisp. It has also not had widespread testing so I would expect it to
>> have several bugs.
>
> I have gotten the following traceback when running in emacs 24.2.1 if
> the pick buffer is the sole window.  It might be related somehow to
> running emacsclient.
>
> Debugger entered--Lisp error: (error "Attempt to delete minibuffer or sole ordinary window")
>   signal(error ("Attempt to delete minibuffer or sole ordinary window"))
>   error("Attempt to delete minibuffer or sole ordinary window")
>   byte-code(" ")
>   delete-window(#<window 327 on *notmuch-pick-thread:00000000000270ce*<2>>)
>   notmuch-pick-close-message-window()
>   notmuch-pick-quit()
>   call-interactively(notmuch-pick-quit nil nil)

Thanks for this (and sorry to be slow responding): I can reproduce this
error without emacsclient. I have a "fix" which I think is ok but I
want to try a bit more testing before posting anything.

Thanks

Mark