If you want webalizer or awstats pages to be available by default for new domains, you can do so by creating:

/usr/local/directadmin/scripts/custom/domain_create_post.sh

In the file add the code

#!/bin/sh
ln -s ../stats /home/$username/domains/$domain/public_html/stats
exit 0;

Then chmod the domain_create_post.sh script to 755.
If you want it to be for awstats, then change the bold stats name to be awstats instead.

If you want to avoid download interruptions during apache restarts, apache has to be changed to restart gracefully.
To do that, you’ll need to change your httpd boot script.
The path for your script will vary depending on your OS.
For FreeBsd it’s:
/usr/local/etc/rc.d/httpd
For all other OS’s, it’s:
/etc/init.d/httpd
As for the actual change, you’ll edit the httpd boot script for your system, find this code:

restart)
  stop
  waitforexit "httpd" 20
  start
  ;;

and change it to read:

restart)
  kill -USR1 `cat $PIDFILE`
  ;;

Note, this is not tested as much, so you’ll need to keep an eye on things until you’re satisfied that it’s stable.
An apache restart will no longer start apache if it’s stopped. You must "start" it, as the graceful restart only works on already running processes.

You can check the current version of apache by running

httpd -v

If you wish to update your 1.3 version of apache to the most recent, run the following:

cd /usr/local/directadmin/customapache
./build clean
./build update
./build apache_mod_ssl

If you’re using apache 2.x, use "./build apache_2" instead of apache_mod_ssl.
This should update both the configure options and the version of apache to the most recent version. Once the update has completed, you’ll need to restart apache:
RedHat:

/sbin/service httpd restart

FreeBSD:

/usr/local/etc/rc.d/httpd restart

If you reinstall DA (./directadmin i) on a live box, your /etc/httpd/conf/httpd.conf file will get overwritten and emptied of all data. You’ll need to read all of the Include lines for your users so that their sites show up (you’ll be seeing the apache pages, or the shared IP pages instead)
Type:

cd /usr/local/directadmin/data/users
for i in `ls`; do { echo "Include /usr/local/directadmin/data/users/$i/httpd.conf" >> /etc/httpd/conf/httpd.conf; }; done;

Note that this add the include lines for *all* users.. so if you’ve added users to DA after you ran the "./directadmin i", you’ll end up with duplicates. Make sure you don’t have duplicate Include lines.. (apache won’t restart, it will let you know)

One common problem people have is an incorrectly setup mail system. Here is a list of rules that must be followed:
1) hostname must not match any domain that is being used on the system. Example, if you have a domain called domain.com and you want to recieve mail on user@domain.com, you must *not* set your hostname to domain.com. We recommend using server.domain.com instead. You must make sure that you add the A record for server.domain.com so that it resolves.
2) The hostname must be in the /etc/virtual/domains file.
3) The hostname must *not* be in the /etc/virtual/domainowners file.
4) The hostname must resolve. If not, add the required A records to the dns zone such that it does.
5) The directory /etc/virtual/hostname must exist.. (eg: /etc/virtual/server.domain.com). It must not contain any files.
6) Any domains that you want to use for email (eg: domain.com) must be in both the /etc/virtual/domains file and the /etc/virtual/domainowners file. The directory /etc/virtual/domain.com must exist and the files /etc/virtual/domain.com/passwd and /etc/virtual/domain.com/aliases exist.
7) File permissions for virtual pop inboxes should be (not applicable with Dovecot/Maildir):

/var/spool/virtual/domain.com 770 username:mail
/var/spool/virtual/domain.com/* 660 username:mail

If you’ve made any changes to you /etc/exim.conf file and require a fresh copy, you can retrieve one with this guide:
http://help.directadmin.com/item.php?id=51
Ensure your hostname does not contain any upper case letters.
9) Make sure that your main server IP has a reverse lookup on it.