mutt reply function returns empty header fields - mutt

Question

I have been using mutt for quite some time but I have reconfigured it for use with offlineimap. The problem is now that when I reply to an email the header fields "To, From, CC Subject ..." are left empty and it is impossible to send the reply. I have to paste the fields in by hand which is kind of annoying (what do we have computers for?).
Any hints, for I have not got a clue how to debug this problem.
Thanks
my muttrc
======================================================
# Boring details
set realname = "Ivo Keel"
set from = "<myid>#gmail.com"
set use_from = yes
# fills headers on reply
set fast_reply = yes
set envelope_from ="yes"
# Check for new mail in the folders
set mail_check=60 # mutt checks for new mails on every keystroke
# but not more often then once in 5 seconds
set beep_new = yes
# Use a signature
set signature="~/.signature"
# mailcap
set mailcap_path="~/.config/mutt/mailcap"
# Use msmtp rather than sendmail. Check that
# the path is correct for your system:
set sendmail="/usr/bin/msmtp"
# If not set in ~/.bashrc:
set spoolfile = "~/.maildir/"
set print_command="/usr/bin/muttprint %s"
set print_split set print="yes"
set sleep_time = 0
set reply_to = yes
#======================================================#
# Folders
set mbox_type=Maildir
#set mbox="~/.maildir/"
set folder="~/.maildir/" # Local mailboxes stored here
mailboxes =c32t/inbox =hibury/inbox =inbox
set record="+/hibury/sent/" # Where to store sent messages
set postponed="+/hibury/drafts/" # Where to store draft messages
#set move=no # Don't move mail from spool
set mask="!^\\.[^.]"
#======================================================#
# What to show and order of headers
ignore *
unignore Date: From: User-Agent: \
Cc: Reply-To: Subject: Mail-Followup-To:
hdr_order Date From Subject To CC
set sort=threads
set sort_browser=reverse-date
set sort_aux=reverse-last-date-received
#======================================================#
# which editor do you want to use?
# vim of course!
set editor="vim"
set edit_headers=yes # See the headers when editing
#======================================================#
# Aliases
set alias_file = ~/.config/mutt/alias # In their own file
source ~/.config/mutt/alias # Source them
set sort_alias=alias # Sort alphabetically
# Odds and ends
set markers # mark wrapped lines of text in the pager with a +
set smart_wrap # Don't wrap mid-word
set pager_context=5 # Retain 5 lines of previous page when scrolling.
set status_on_top # Status bar on top.
push <show-version> # Shows mutt version at startup
set duplicate_threads = yes
#email addresses with esc-1 and esc-2. Sets the status bar at the
# top too so you know which from address you're using
set mailcap_path = ~/.config/mutt/mailcap auto_view text/html
set query_command="abook --mutt-query '%s'"
# Pager View Options ---------------------------------
set pager_index_lines = 10 # number of index lines to show
set pager_context = 3 # number of context lines to show
set pager_stop # don't go to next message automatically
set menu_scroll # scroll in menus
set tilde # show tildes like in vim
unset markers # no ugly plus signs
set quote_regexp = "^( {0,4}[>|:#%]| {0,4}[a-z0-9]+[>|]+)+"
alternative_order text/plain text/enriched text/html
bind pager R group-reply
# View attachments properly.
bind attach <return> view-mailcap
#Skip some options
set include=yes
set forward_quote=yes
set copy=yes
set delete=yes
set confirmappend=no
#--------------------------------------------------------------------------
# Other configuration files
#--------------------------------------------------------------------------
#source ~/.config/mutt/account_hooks
#source ~/.config/mutt/folder_hooks
source ~/.config/mutt/colors
source ~/.config/mutt/sidebar
#source ~/.config/mutt/gpg
source ~/.config/mutt/macros
source ~/.config/mutt/lists
source ~/.config/mutt/alias
END of muttrc

Answer 1

Allowing mutt to automatically fill the From: header is done by adding:
set use_from = yes
to your .muttrc and allowing it to automatically fill the To: and Subject: header can be done by putting:
set fast_reply = yes
in your .muttrc. Those two options are very common, if you don't have them, you should consider looking at some of the .muttrc configurations available online to find other classical options (noconfirmappend, reverse_alias, sort=threads, etc.) which will greatly improve your mutt experience.
The CC: header will not be filled if you use the "reply" command instead of the "group-reply" one (the default keyboard shortcut is g).

Answer 2

I had this problem, but it turned out to be a problem with my workflow (the buggy system located between the keyboard and chair). Perhaps this was also your issue?
When I reply to a message in Mutt, Mutt drops me into a text editor session with pre-populated reply headers, like this:
1: From: Steve HHH <steve#hhhdomain.com>
2: To: Jonny Appleseed <jonny#hhhdomain.com>
3: Cc:
4: Bcc:
5: Subject: Re: Good morning
6: Reply-To:
7: In-Reply-To: <CABSQ23i=yOa3GUwvbUPmHE+_i1_gLw#mail.gmail.com>
8:
9: On Mon, Sep 29, 2014 at 11:52:04AM -0700, Jonny Appleseed wrote:
10: > LOL
My mistake was to start typing the reply on line one. Mutt needs those headers on lines 1-7 (and the newline on line 8?) to stay intact. If I enter my reply on line nine, the reply fields are correctly populated when I exit the editor and arrive at the Compose menu.