Magento install was redirecting all 'non-www' urls to the root home page. I found these questions on the same subject:
Redirected to the Homepage when add www. in any URL
Redirected to the Homepage when removed www. from URL
So I have disabled 'Auto-redirect to Base URL' and the redirect was removed. I've now tried to add my own redirect in htaccess to redirect non www URLs to their www equivalents, but they are simply redirecting to root again.
This is the code I have used in htaccess
RewriteCond %{HTTP_HOST} ^example.com.au$ [NC]
RewriteRule ^(.*)$ http://www.exmaple.com.au/$1 [R=301,L]
I have used this code on hundreds of website and it usually works, so there must be something Magento specific causing the issue, either in the htaccess or elsewhere.
Here is the rest of the htaccess:
############################################
## uncomment these lines for CGI mode
## make sure to specify the correct cgi php binary file name
## it might be /cgi-bin/php-cgi
# Action php5-cgi /cgi-bin/php5-cgi
# AddHandler php5-cgi .php
############################################
## GoDaddy specific options
# Options -MultiViews
## you might also need to add this line to php.ini
## cgi.fix_pathinfo = 1
## if it still doesn't work, rename php.ini to php5.ini
############################################
## this line is specific for 1and1 hosting
#AddType x-mapp-php5 .php
#AddHandler x-mapp-php5 .php
############################################
## default index file
DirectoryIndex index.php
<IfModule mod_php5.c>
############################################
## adjust memory limit
# php_value memory_limit 64M
php_value memory_limit 256M
php_value max_execution_time 18000
############################################
## disable magic quotes for php request vars
php_flag magic_quotes_gpc off
############################################
## disable automatic session start
## before autoload was initialized
php_flag session.auto_start off
############################################
## enable resulting html compression
php_flag zlib.output_compression on
###########################################
# disable user agent verification to not break multiple image upload
php_flag suhosin.session.cryptua off
###########################################
# turn off compatibility with PHP4 when dealing with objects
php_flag zend.ze1_compatibility_mode Off
</IfModule>
<IfModule mod_security.c>
###########################################
# disable POST processing to not break multiple image upload
SecFilterEngine Off
SecFilterScanPOST Off
</IfModule>
<IfModule mod_deflate.c>
############################################
## enable apache served files compression
## http://developer.yahoo.com/performance/rules.html#gzip
# Insert filter on all content
SetOutputFilter DEFLATE
# Insert filter on selected content types only
AddOutputFilterByType DEFLATE text/html text/plain text/xml text/css text/javascript
# Netscape 4.x has some problems...
BrowserMatch ^Mozilla/4 gzip-only-text/html
# Netscape 4.06-4.08 have some more problems
BrowserMatch ^Mozilla/4\.0[678] no-gzip
# MSIE masquerades as Netscape, but it is fine
BrowserMatch \bMSIE !no-gzip !gzip-only-text/html
# Don't compress images
SetEnvIfNoCase Request_URI \.(?:gif|jpe?g|png)$ no-gzip dont-vary
# Make sure proxies don't deliver the wrong content
Header append Vary User-Agent env=!dont-vary
</IfModule>
<IfModule mod_ssl.c>
############################################
## make HTTPS env vars available for CGI mode
SSLOptions StdEnvVars
</IfModule>
<IfModule mod_rewrite.c>
############################################
## enable rewrites
#Options +FollowSymLinks
RewriteEngine on
############################################
## you can put here your magento root folder
## path relative to web root
#RewriteBase /magento/
############################################
## workaround for HTTP authorization
## in CGI environment
RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]
############################################
## always send 404 on missing files in these folders
#RewriteCond %{HTTP_HOST} !^www\.eternalsource\.com\.au [NC]
#RewriteRule ^(.*)$ [R=301,L]
#RewriteCond %{REQUEST_URI} !^/(media|skin|js)/
############################################
########## MOBILE ###########
#SetEnv isAndroidTablet=NO
#BrowserMatchNoCase Android isAndroidTablet=YES
#BrowserMatchNoCase "Mobile Safari" isAndroidTablet=NO
# Check if this is the noredirect query string
RewriteCond %{QUERY_STRING} (^|&)m=0(&|$)
# Set a cookie, and skip the next rule
RewriteRule ^ - [CO=mredir:0:www.eternalsource.com.au]
# Check if this looks like a mobile device
# (You could add another [OR] to the second one and add in what you
# had to check, but I believe most mobile devices should send at
# least one of these headers)
RewriteCond %{HTTP:x-wap-profile} !^$ [OR]
RewriteCond %{HTTP:Profile} !^$ [OR]
RewriteCond %{HTTP_USER_AGENT} "acs|alav|alca|amoi|audi|aste|avan|benq|bird|blac|blaz|brew|cell|cldc|cmd-" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "dang|doco|eric|hipt|inno|ipaq|java|jigs|kddi|keji|leno|lg-c|lg-d|lg-g|lge-" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "maui|maxo|midp|mits|mmef|mobi|mot-|moto|mwbp|nec-|newt|noki|opwv" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "palm|pana|pant|pdxg|phil|play|pluc|port|prox|qtek|qwap|sage|sams|sany" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "sch-|sec-|send|seri|sgh-|shar|sie-|siem|smal|smar|sony|sph-|symb|t-mo" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "teli|tim-|tosh|tsm-|upg1|upsi|vk-v|voda|w3cs|wap-|wapa|wapi" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "wapp|wapr|webc|winw|winw|xda|xda-" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "up.browser|up.link|windowssce|iemobile|mini|mmp" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "symbian|midp|wap|phone|pocket|mobile|pda|psp" [NC]
RewriteCond %{HTTP_USER_AGENT} !ipad|tablet|android [NC]
RewriteCond %{ENV:isAndroidTablet} !=YES
RewriteCond %{HTTP_USER_AGENT} !macintosh [NC]
# Check if we're not already on the mobile site
RewriteCond %{HTTP_HOST} !^m\.
# Can not read and write cookie in same request, must duplicate condition
RewriteCond %{QUERY_STRING} !(^|&)m=0(&|$)
# Check to make sure we haven't set the cookie before
RewriteCond %{HTTP_COOKIE} !^.*mredir=0.*$ [NC]
# Now redirect to the mobile site
RewriteRule ^(.*)$ http://m.eternalsource.com.au/$1 [R,L]
RewriteCond %{HTTP_HOST} ^m.eternalsource.com.au
RewriteRule ^ - [E=MAGE_RUN_CODE:eternalsource_mobile]
RewriteRule ^ - [E=MAGE_RUN_TYPE:website]
## never rewrite for existing files, directories and links
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-l
############################################
## rewrite everything else to index.php
RewriteRule .* index.php [L]
</IfModule>
############################################
## Prevent character encoding issues from server overrides
## If you still have problems, use the second line instead
AddDefaultCharset Off
#AddDefaultCharset UTF-8
<IfModule mod_expires.c>
############################################
## Add default Expires header
## http://developer.yahoo.com/performance/rules.html#expires
ExpiresActive On
ExpiresDefault "access plus 1 year"
</IfModule>
############################################
## By default allow all access
Order allow,deny
Allow from all
###########################################
## Deny access to release notes to prevent disclosure of the installed Magento version
<Files RELEASE_NOTES.txt>
order allow,deny
deny from all
</Files>
############################################
## If running in cluster environment, uncomment this
## http://developer.yahoo.com/performance/rules.html#etags
FileETag none
##############################################
# 301 redirect of duplicate content page
Redirect 301 /contact-us http://www.eternalsource.com.au/contacts/
# rediect 'non-www' to www prefix
RewriteCond %{HTTP_HOST} ^example.com.au$ [NC]
RewriteRule ^(.*)$ http://www.example.com.au/$1 [R=301,L]
