.htaccess Remove .aspx ending on wordpress

Solution:

# BEGIN WordPress

RewriteEngine On
RewriteBase /

# Remove .aspx from old URLs
RewriteCond %{THE_REQUEST} \s/+(.*?/)?(?:index)?(.*?)\.aspx[\s?] [NC]
RewriteRule ^ /%1%2 [R=301,L,NE]

RewriteRule ^index\.php$ – [L]

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]

# END WordPress