Hello Jason,
Our posts overlaped...
Well the same host is relevant, as CF 7 behaves different.
For example, the client I mentioned changed its hosting company. Before he had no problem sending sucessfull forms.
The From-Field was looing like that at the old host:
[your-name],< [email]>
The new host doesn't work with this code.
It has to be formed like this:
[your-name] <[email]>
I did a lot of testing, and none failed for me, but for my client.
I don't want to change the From-Field to a static email-adress right now, as I want to give my client the oportunity to hit the reply-button in his email-client. Only as a last oportunity.
I will install Postman today and do some testing.