TOPIC: Unable to instantiate email for Yahoo

We've just upgraded to the latest version of DT Register, and I'm still having this problem. When I set up confirmation emails to be sent to guests registering for an event, at the top of the Emails page I put a Subject and From Email for those emails.
This works great, as long as the From Email isn't a Yahoo.com account. If it is, when I hit the final Submit button, I see the Confirmation page, but above it is the note "Unable to instantiate email." I get an email with registration information, but the registrant gets nothing.
What could be causing this? And what can I do about it?

I've tried it with several Yahoo addresses, with the same effect. As soon as I use another email, it's fine.

This is not actually a DT Register problem... but one tied to your web host. DT Reg puts the emails together, but they are actually sent FROM your host mail server. The settings for this are in Joomla's global configuration. You need to touch base with your host as they likely have restrictions in place on what domains can be used to SEND emails on their server. It's not surprising that you'd have an issue sending email from something as "generic" as yahoo.com.

Ask your host if there are any changes that could be made in your global configuration of Joomla or in your hosting account to allow that to work. If not, you can try a different host or just use approved email domains for sending emails.