SMTP help

SMTP help

Hi everybody.
Zoho always worked perfect for me, but today 4 hours ago I'm trying to figure out why zoho smtp doesn't work with this.

I've installed xampp on my server with a complete version of a web with forms for user register. 
That web allows me to change the smtp server, user, password, port and secure connection.

I tried with gmail smtp and it works perfect, but with zoho smtp I received "an error with smtp"  and doesn't work. I don't know where I've got to go to see the error. 
I tried with SSL 465; TLS 587, another emails and doesn't work. I enabled openssl.dll extension at php.ini, php_smtp.dll, and set SMTP = smtp.zoho.com - smtp_port = 465.
Doesn't work. Can you help me?

Thanks so much. Zoho is great!