HTTPS and Remove index.php on CodeIgniter

I am using codeigniter framework,set .htaccess file to remove index.php and trying to enable HTTPS protocol for the server, and something happened.
HTTP:

1. Everything is okay, when I access http://www.example.com/controller/method orhttp://www.example.com/index.php/controller/method
   

HTTPS:

1. Everything is okay, when I access https://www.example.com/index.php/controller/method
   
   
2. Got 404 not found when I access https://www.example.com/controller/method
   

I think that is .htaccess file problem, it is look like htaccess file not working for HTTPS protocol.
.htaccess file of my site.

Code:

DirectoryIndex index.php
RewriteEngine on

RewriteCond %{HTTPS} off
RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]

RewriteCond $1 !^(index\.php|(.*)\.swf|forums|images|css|downloads|js|robots\.txt|favicon\.ico)
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ ./index.php?$1 [L,QSA]

Is something wrong? thanks a lot.

RewriteCond $1 !^(index\.php|(.*)\.swf|forums|images|css|downloads|js|robots\.txt|favicon\.ico)
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ ./index.php?$1 [L,QSA]

replace to

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*) index.php/$1

RewriteCond $1 !^(index\.php|(.*)\.swf|forums|images|css|downloads|js|robots\.txt|favicon\.ico)
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ ./index.php?$1 [L,QSA]

replace to

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*) index.php/$1

Still not work

RewriteCond $1 !^(index\.php|(.*)\.swf|forums|images|css|downloads|js|robots\.txt|favicon\.ico)
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ ./index.php?$1 [L,QSA]

replace to

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*) index.php/$1

Still not work

It's in your config file... http:// or https://

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