Have you just moved a WordPress based website onto your VPS running Plesk and can’t get rid of the redirect loop even after changing everything you can think of both in your WordPress settings and .htaccess?
Well worry not my friend because this simple solution will most likely fix your website.
1) From your Plesk Panel select “Subscriptions”:
2) Select the domain you’re currently using and click on “Open in control panel”:
3)Go to “Hosting settings”:
4) Look for “Preferred domain” and select ‘none’:
That should do it, save your settings and reload your website (hit CTRL+R a couple of times to make sure the website is not loaded from cache).