Received from South Texas Hamfest at 9/17/2018 07:04 PM UTC:
* <en5rp@...>: Invalid email address
* <kirbygray@...>: Invalid email address
* <w5rex2@...>: Invalid email address
Using the invite function I keep getting LOTS of "Invalid email address" after submitting. But, these are KNOWN good addresses.
WHEN were they known to be good addresses? In the distant past or very recently? If not very recently, you might want to try sending mail to them from your own email address, not from Groups.io, and see what happens.
Jim H