What is .htaccess?


.htaccess is a configuration file for use on web
servers running the Apache Web Server software.
When a .htaccess file is placed in a directory which
is in turn 'loaded via the Apache Web Server', then
the .htaccess file is detected and executed by the
Apache Web Server software. These .htaccess files can be used to alter the configuration of the Apache Web Server software to enable/disable additional functionality and features that the Apache Web Server software has to offer. These facilities include basic redirect functionality, for instance if a 404 file not found error occurs, or for more advanced functions such as content password protection or image hot link prevention.

How to use .htaccess
'.htaccess' is the filename in full, it is not a file
extension. For instance, you would not create a file
called, 'file.htaccess', it is simply called, '.htaccess'.
This file will take effect when placed in any
directory which is then in turn loaded via the
Apache Web Server software. The file will take
effect over the entire directory it is placed in and all
files and subdirectories within the specified
directory.
You can create a .htaccess file using any good text
editor such as TextPad, UltraEdit, Microsoft
WordPad and similar (you cannot use Microsoft
NotePad).
Here is an example of what you might include in a
.htaccess file.
AuthName "Member's Area Name"
AuthUserFile /path/to/password/file/.htpasswd
AuthType Basic
require valid-user
ErrorDocument 401 /error_pages/401.html
AddHandler server-parsed .html
This is a fairly advanced example: it enables
password protection on the directory; it offers
redirection to a custom error page if a user fails to
login correctly; and it enables SSI (server side
includes) for use with '.html' files. Please don't be
put off, it's very simple once you gain a basic
understanding and this article provides examples
which are ready to go - simply copy, paste and
customise. Examples are explained line by line so it
is clear exactly what each line does and why you
need it.
Once you have created a .htaccess file, which may
look similar to the one shown above (or may simply
contain one line), you need to upload it. This should
be done using a FTP (file transfer protocol)
program. You should already have one which you
will have used to upload your web site content. If
not, many are available free of charge from web
sites such as 'Download.com' and we can
recommend 'CuteFTP' and 'WSFTP'.
When uploading your .htaccess files, it is very
important you upload the file in 'ASCII' mode.
'ASCII' and 'BINARY' are different methods of
transferring data and it is important .htaccess files
are transferred in 'ASCII' mode and not 'BINARY'. It
is likely your FTP software will default to 'BINARY'
so look for a 'Transfer Mode' or 'Transfer Type'
option in the menus.
Upload the .htaccess file to the directory you would
like it to take effect over. Now visit this directory
using your web browser as you would for any other
document on your web site and check it has
worked correctly.
Note, when you upload your .htaccess file it may
not appear in the directory listings for files on your
web site. Do not worry; this means your server or
FTP software is hiding them which should not be an
issue.
A possible cause of error is if the file permissions
on the .htaccess file are not set correctly. This only
occurs on certain servers, but you may like to
change the permissions on the file to '755' or
'executable'. You can do this with your FTP
software, look for a 'File Permissions' or 'CHMOD'
option, and input '0755'.
If your .htaccess file does not work, you should
contact your system administrator or web hosting
company and ensure they have enabled .htaccess
within your account. Some web hosting companies
do not allow use without permission. If errors
persist, consult this article for advice, or contact
your system administrator for advice.

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