For my site I have a RewriteRule that points the URL http://www.mysite.com/work to a work.php file. I also have a directory called \"work\" that has files in it, like project1.p
Try this rule:
RewriteCond %{REQUEST_FILENAME}.php -f
RewriteRule .* $0.php [L]
Try this:
RewriteEngin On
RewriteBase /
RewriteRule ^work$ /work.php [QSA,L]
That will ensure that http://www.mysite.com/work (no trailing slash) will go to your work.php file.
If you also want http://www.mysite.com/work/ (with trailing slash) to go work.php, add this line just above the last RewriteRule.
RewriteRule ^work/$ /work [R=301,QSA,L]
That will redirect it to the URL with no trailing slash thus, displaying the work.php file.
UPDATE: Since you already have a RewriteBase directive, just put the RewriteRule line(s) right after your RewriteBase but before your RewriteRule as the rule you're using a catch-all and will match everything.
This is the answer to your question. It works for me.
RewriteEngine On
RewriteBase /
RewriteRule ^([a-z]+)$ $1.php [L]
Simply remove beta/