Verification Email Not Sent

I have been going through purgatory trying to get email verification to work. I’ve created a bare bones test site with the following plugins installed and enabled:
Ultimate Member
WP Mail SMTP Pro
There are no other plugins active.

In General Settings:
Anyone can register is checked.
New User Default Role is set to Subscriber.

Under Ultimate Member User Roles:
Subscriber->Registration Status is set to “Require Email Activation”

I register a new user “yojimbo” with a valid email address. and receive the message “Thanks for registering with xxxxx.org. Please look for an email and follow the instructions to verify your membership.”

I receive no email verification. When I attempt to log in a get the message “Your account is awaiting e-mail verification.”

I login is admin and delete user “yojimbo”. yojimbo receives an email with subject “You account has been deleted” and body “xxxxx.org TEST SITE
Your account has been deleted.
All your personal details and any uploads have been permanently removed.
If your account has been deleted by accident please contact us.

I can see in the “[xxxxx.org TEST SITE] New user account” sent to me ad “admin” and “Your account has been deleted” sent to yojimbo. No record of an activation email.

I am using WP SMTP Pro to send to my private email server via SMTP/TLS. It clearly works; I get all other emails.

I found this topic, “https://wordpress.org/support/topic/registration-confirmation-email-is-not-sent-2/” which had one user solve the problem and two others report it with no response. Thread is now closed.

I’m not sure what more I can do to troubleshoot this without getting down into the bowels of the code to an extent that makes the whole thing just not worth it.

Please help! This is a community project turned evil and for this much effort I really would rather make money!

Thanks much in advance.

Jim “L. Viejo” Siler