Some minor edits.

.doom.d/config.el

@@ -1,9 +1,25 @@
 ;;; .doom.d/config.el -*- lexical-binding: t; -*-
 
-;; Place your private configuration here
+;; Place your private configuration here!
+;;  ____ _____ 
+;; |  _ \_   _|  Derek Taylor (DistroTube)
+;; | | | || |      http://www.youtube.com/c/DistroTube
+;; | |_| || |      http://www.gitlab.com/dwt1/
+;; |____/ |_|
+;;        
+;; A customized config for Doom Emacs (https://github.com/hlissner/doom-emacs)     
+;; Modified by Derek Taylor (http://www.gitlab.com/dwt1/)
 
+;; Setting the font.
 (setq doom-font (font-spec :family "Mononoki Nerd Font Mono" :size 15))
+
+;; Setting the theme
 (setq doom-theme 'doom-dracula)
+
+;; Setting the neotree width to be adjustable.
+(setq neo-window-fixed-size nil)
+
+;; Setting the indent guides to show an arrow.
 (def-package! highlight-indent-guides
   :commands highlight-indent-guides-mode
   :hook (prog-mode . highlight-indent-guides-mode)
@@ -13,3 +29,35 @@
         highlight-indent-guides-delay 0.01
         highlight-indent-guides-responsive 'top
         highlight-indent-guides-auto-enabled nil))
+        
+;; Setting up mu4e which is an email client that works within emacs.
+;; You must install mu4e and mbsync through your Linux distribution's
+;; package manager.
+(require 'mu4e)
+(setq mu4e-get-mail-command "mbsync -c ~/.emacs.d/mu4e/.mbsyncrc -a"
+      mu4e-update-interval  300)
+      
+;; Fields that are auto-filled in email such as the full name of the
+;; sender, the salutation and signature.
+(setq
+   user-mail-address "derek@distrotube.com"
+   user-full-name  "Derek Taylor"
+   mu4e-compose-signature
+    (concat
+      "Derek Taylor\n"
+      "http://www.youtube.com/DistroTube\n"))
+
+;; Setting up smtp for sending mail. Make sure the gnutls command 
+;; line utils are installed. Package 'gnutls-bin' in Debian/Ubuntu, 
+;; and 'gnutls' in Arch.
+(require 'smtpmail)
+(setq message-send-mail-function 'smtpmail-send-it
+   starttls-use-gnutls t
+   smtpmail-starttls-credentials '(("smtp.1and1.com" 587 nil nil))
+   smtpmail-auth-credentials
+     '(("smtp.1and1.com" 587 "derek@distrotube.com" nil))
+   smtpmail-default-smtp-server "smtp.1and1.com"
+   smtpmail-smtp-server "smtp.1and1.com"
+   smtpmail-smtp-service 587)
+;; don't keep message buffers around
+(setq message-kill-buffer-on-exit t)

.doom.d/init.el

@@ -8,6 +8,9 @@
 ;; More information about these modules (and what flags they support) can be
 ;; found in modules/README.org.
 
+        
+(add-to-list 'load-path "/usr/local/share/emacs/site-lisp/mu4e")
+
 (doom! :input
        ;;chinese
        ;;japanese
@@ -29,7 +32,7 @@
        indent-guides   ; highlighted indent columns
        modeline          ; snazzy, Atom-inspired modeline, plus API
        nav-flash         ; blink the current line after jumping
-       ;;neotree           ; a project drawer, like NERDTree for vim
+       neotree           ; a project drawer, like NERDTree for vim
        ophints           ; highlight the region an operation acts on
        (popup            ; tame sudden yet inevitable temporary windows
         +all             ; catch all popups that start with an asterix
@@ -155,7 +158,7 @@
        web                 ; the tubes
 
        :email
-       (mu4e +gmail)
+       ;;(mu4e +gmail)
        ;;notmuch
        ;;(wanderlust +gmail)