Magento – Magento admin URL redirecting to index.php/admin, resulting in redirect loop

adminmagento-1.7redirect

If I enter URL

https://server.com/admin

It ends up redirecting to:

https://server.com/index.php/admin

and I end up with "This webpage has a redirect loop".

a) Is this redirect url correct? Doesn't look to be valid.
b) Where do I correct it?

/index.php/admin is normal and should work. Check your Magento .htaccess in root. Mostly you have to set the web root.

############################################
## you can put here your magento root folder
## path relative to web root

    RewriteBase /

Your Base URL should be http://...

Your secure Base URL should be https://...