Suddenly order Confirmation emails not being sent to admin address

I've got it set to send copies of most email events to my main email address and they're distributed to folders with filters.

Never had a problem with it before, but an issue popped up last night.

Tried to send out half a dozen order updates, changed status to shipped, update customer. I got "Unable to connect: SMTP error" on 5 of the 6 of them. The last one worked.

This afternoon, half a dozen orders came through. I only got one of the NEW ORDER emails.

Host says it's the script....but I fail to see the logic in that if nothing is changing on this end.

Downloaded the entire site and compared it with an earlier backup I made the first of the month. All the files are identical.

I gotta be missing something here....any ideas?

When something "suddenly" stops working with email, it's always a factor of something wrong on the server that's handling the email.
Specifically, an "Unable to connect" message means just what it says: when Zen Cart attempted to connect to the mail server so give it a message to deliver, the connection wasn't possible. It might have been actively rejected or maybe the mailserver itself was too busy to respond to the request to login and pass on a message.
And, when "some" work fine but others do not, then it's also a strong indicator that the problem is on the mailserver end, and not the Zen Cart end.

So, whoever manages your mailserver is the one who needs to investigate the problems they're having with providing reliable service.