'htaccess redirect all pages to single page

I want to redirect all of my old domain request to my new domain using htaccess file. Below is what I am using but it does not work if the page is not on the new site. For example google index about.htm on the old site but on the new site it does not exist. I would like it to just go to the root in all cases. I know this is not ideal for seo but I don't want any 404s. Any suggestions?

Redirect 301 / http://www.thenewdomain.com/


Solution 1:[1]

If your aim is to redirect all pages to a single maintenance page (as the title could suggest also this), then use:

RewriteEngine on
RewriteCond %{REQUEST_URI} !/maintenance.php$ 
RewriteCond %{REMOTE_HOST} !^000\.000\.000\.000
RewriteRule $ /maintenance.php [R=302,L] 

Where 000 000 000 000 should be replaced by your ip adress.

Source:

http://www.techiecorner.com/97/redirect-to-maintenance-page-during-upgrade-using-htaccess/

Solution 2:[2]

This will direct everything from the old host to the root of the new host:

RewriteEngine on
RewriteCond %{http_host} ^www.old.com [NC,OR]
RewriteCond %{http_host} ^old.com [NC]
RewriteRule ^(.*)$ http://www.thenewdomain.org/ [R=301,NC,L]

Solution 3:[3]

RewriteEngine on
RewriteCond %{HTTP_HOST} ^(www\.)?olddomain\.com$ [NC]
RewriteRule ^(.*)$ "http://www.thenewdomain.com/" [R=301,L]

Solution 4:[4]

Add this for pages not currently on your site...

ErrorDocument 404 http://example.com/

Along with your Redirect 301 / http://www.thenewdomain.com/ that should cover all the bases...

Good luck!

Solution 5:[5]

HTAccess to send all pages of a website to one page. This worked for me:

ErrorDocument 404 /page-name.php

or to a different domain...

RedirectMatch 301 ^/.*$ https://www.example-domain.com/page-name.php

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution Source
Solution 1 MattAllegro
Solution 2 bjudson
Solution 3 Marco Demaio
Solution 4 WizarDave Akins
Solution 5