htaccess to change url - apache

Question

I have the following code in my .htacess but it didn't work right. Is it because mod-rewrite is no "on", if so, how can i check?
Options +FollowSymlinks
RewriteEngine on
RewriteRule ^(.*)\$ $1.php [nc]
I wanted to rename my address, example:
http://www.abc.com -> http://www.abc.com
http://abc.com -> http://www.abc.com
http://www.abc.com/123.html -> http://www.abc.com/123
http://www.abc.com/12-12-12.html -> http://www.abc.com/12-12-12
http://subdomain.abc.com/123.html -> http://subdomain.abc.com/123
Basically removing the extension and ensuring that its www is intact.
Edited:
It was rewrote into
Options +FollowSymlinks
RewriteEngine on
RewriteCond % ^example.com [NC]
RewriteRule ^(.*)$ http://www.example.com/$1 [L,R=301]
RewriteRule ^(.*).php $1
but still not working

Answer 1

Step 1.
Change all of your links to have the .html removed from links. Make sure you have Multiviews turned off:
Options -Multiviews
Step 2.
You need rules to redirect the browser when there is a www missing from the hostname:
RewriteCond %{HTTP_HOST} ^example\.com$ [NC]
RewriteRule ^(.*)$ http://www.example.com/$1 [L,R=301]
Step 3.
You need rules to redirect the browser when a URL is requested with .html or .php with the extensions removed:
RewriteCond %{THE_REQUEST} ^(GET|HEAD)\ /([^\ ]+)\.(php|html?)
RewriteCond %{REQUEST_FILENAME} -f
RewriteRule ^ /%2 [L,R=301]
Step 4.
You need rules to internally rewrite the URI if the request was actually for a php or html file:
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}.php -f
RewriteRule ^(.*)$ /$1.php [L]
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}.htm -f
RewriteRule ^(.*)$ /$1.htm [L]
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}.html -f
RewriteRule ^(.*)$ /$1.html [L]
.htaccess
So all in all, you should have these rules in your htaccess (ditch any rules you may already have trying to solve this issue):
# Make sure Multiviews is off
Options -Multiviews
# turn on rewrite engine
RewriteEngine On
# Redirect requests that are missing www and not a subdomain
RewriteCond %{HTTP_HOST} ^example\.com$ [NC]
RewriteRule ^(.*)$ http://www.example.com/$1 [L,R=301]
# Redirect if requests is for a .htm, .html, or .php
RewriteCond %{THE_REQUEST} ^(GET|HEAD)\ /([^\ ]+)\.(php|html?)
RewriteCond %{REQUEST_FILENAME} -f
RewriteRule ^ /%2 [L,R=301]
# rewrite to the proper extension if such a file exists
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}.php -f
RewriteRule ^(.*)$ /$1.php [L]
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}.htm -f
RewriteRule ^(.*)$ /$1.htm [L]
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}.html -f
RewriteRule ^(.*)$ /$1.html [L]
So altogether:
if browser URL address bar says: http://example.com/index.html it will be redirected to http://www.example.com/index
if browser URL address bar says: http://www.example.com/index it will be shown the content at http://www.example.com/index.html (or index.php if that exists). Address bar remains unchanged.
if browser URL address bar says: http://foo.example.com/images/image.png you will see the image at /images/image.png. Address bar remains unchanged.
if browser URL address bar says: http://foo.example.com/path/foo/bar.php it will be redirected to http://foo.example.com/path/foo/bar
if browser URL address bar says: http://foo.example.com/path/foo/bar it will be shown the content at http://foo.example.com/path/foo/bar.php. Address bar remains unchanged.

Answer 2

Remove .html:
RewriteRule ^(.*).html $1 [L,QSA]
Add www.:
RewriteCond % ^example.com [NC]
RewriteRule ^(.*)$ http://www.example.com/$1 [L,R=301]

Answer 3

On which hosting is located your website ? Are you sure mod-rewrite is enabled ? Did you contact your host to put it on, if not activated ?
Solution previously posted by androbin (https://stackoverflow.com/a/12553613/1713771) is correct.

Answer 4

The .htaccess file that I use:
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteCond %{HTTPS} !=on
RewriteCond %{HTTP_HOST} ^www\.(.+)$ [NC]
RewriteRule ^(.*)$ http://%1/$1 [R=301,L]
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}\.html -f
RewriteRule ^(.*)$ $1.html
</IfModule>
Which removes the .html file extension and forces www.