IFTTT denied?

This combination worked for me:

First:
Find out the “real” URL of your self-hosted WordPress installation (ie. the FTP folder).
Example: my WordPress blogs is “http://blog.myhomepage.com/login.php”
But the FTP folder is “http://www.myhomepage.com/Wordpress_01/login.php”
So you need to find your real URL.

Second:
When you activate the WordPress channel in IFTTT, be sure to point it to
URL_to_your_Wordpress/xmlrpc.php NOT to URL_to_your_Wordpress/login.php
Example:
put something like this in the URL field when activating the IFTTT wordpress channel: “http://www.myhomepage.com/Wordpress_01/xmlrpc.php”
Then IFTTT should connect to your WordPress.

More here.
http://codex.ww.wp.xz.cn/XML-RPC_Support