Here I am stuck with my htaccess code. I have been trying to figure it out for the last 11 hours why am I getting a redirect loop for the below code.

Options -Indexes +FollowSymLinks
RewriteEngine on

#Check for no www or www
RewriteCond %{HTTP_HOST} ^dummysite.com$ [or]
RewriteCond %{HTTP_HOST} ^www.dummysite.com$ [NC]
RewriteRule . - [E=FIRSTPART:true]

# IE 6
RewriteCond %{HTTP_USER_AGENT} !MSIE\s6

RewriteCond  %{ENV:FIRSTPART}  true
RewriteRule ^(.*)$ https://www.dummysite.com/$1 [R=302,L]

Why the above code results into a redirect loop?

EDIT: What I actually want is that if the user is from IE6 then he should be redirected to http version with www as prefix no matter if he types www or not in the url. And on the other hand if the user is from any other browsers then he should be redirected to a https version with www as prefix no matter if he types www in the url or not.