php - .htaccess Issue : 404 for index -

this .htaccess file in sub-folder...

<ifmodule mod_rewrite.c> rewriteengine on rewriterule ^index\.php$ - [l] rewriterule (.*) ./index.php?id=$1 [l] </ifmodule> 

i want mydomain.com/sub-folder/string processed index.php mydomain.com/sub-folder/?id=string

but getting 404... not sure why. root .htaccess

# begin wordpress <ifmodule mod_rewrite.c> rewriteengine on rewritebase / rewriterule ^index\.php$ - [l] rewritecond %{request_filename} !-f rewritecond %{request_filename} !-d rewriterule . /index.php [l] </ifmodule> # end wordpress 

keep root .htaccess as:

# begin wordpress <ifmodule mod_rewrite.c> rewriteengine on rewritebase /  rewriterule ^(index\.php|sub-folder(/.*)?)$ - [l,nc]  rewritecond %{request_filename} !-f rewritecond %{request_filename} !-d rewriterule . index.php [l] </ifmodule> # end wordpress 

and keep in /sub-folder/.htaccess:

<ifmodule mod_rewrite.c> rewriteengine on rewritebase /sub-folder/  rewriterule ^index\.php$ - [l,nc] rewriterule (.+) index.php?id=$1 [l,qsa] </ifmodule>