Force WordPress SSL HTTPS on Only One Page

RewriteEngine On
Options -Indexes
Options +FollowSymLinks
RewriteBase /

# force https for all URLs matching “subscribe.*
# otherwise normal http request are unmolested
# other methods that force ssl cause 301 redirects on
# all pages
RewriteCond %{HTTPS} =off
RewriteRule ^subscribe https://%{HTTP_HOST}%{REQUEST_URI} [R=301,L]

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
## standard rule but causes redirect loops
#RewriteRule . /index.php [L]
## new rule seems to solve redirect loop problems
RewriteRule ^(?!index\.php) /index.php [L]