Using Zoho servers to email through QuickBooks

Using Zoho servers to email through QuickBooks

I've just switched to Zoho, and so far I'm impressed. I do seem to be having one issue though. I use QuickBooks and with my previous email provider I had the "Send Form" preferences set up with their smtp details in order to email invoices from within QuickBooks. It's not that tricky, there's just an account name (email address), server name, port number and check box for SSL. I've set it up using the primary email address of an account, smtp.zoho.com, port 465 and the SSL box checked. But, it just keeps coming back and saying it can't send the emails because either the password is wrong or the server is unavailable. It was working with the previous provider, and I have an email client (on a different machine) sending and receiving email fine.

Any ideas?