Forum Password Reset Email Rejected Sender verify failed

[fireblade 5]

The Server you are using to send these emails appears to be producing "Sender verify failed" errors

which suggest some misconfiguration

example error log from my email account (identifiable information <removed>)
 

Event:	rejected
User:	-remote-
Domain:
From Address:	bounce+ce1133.cdb2f-<removed>@wurmonline.com
Sender:
Sent Time:	Apr 28, 2019, 1:52:01 AM
Sender Host:	rs248.mailgun.us
Sender IP:	209.61.151.248
Authentication:	unauthorized
Spam Score:	0
Recipient:	<removed>
Delivery User:	<removed>
Delivery Domain:	<removed>
Delivered To:
Router:	reject
Transport:	**rejected**
Out Time:	Apr 28, 2019, 1:52:01 AM
ID:	1hKY3O-000BHh-T7
Delivery Host:	rs248.mailgun.us
Delivery IP:	209.61.151.248
Size:	0 bytes
Result:	Sender verify failed

it appears to me that your DNS doesnt have MX records configured for rs248.mailgun.us

 

C:\Users\fireblade>nslookup -q=mx wurmonline.com
....

Non-authoritative answer:
wurmonline.com  MX preference = 50, mail exchanger = aspmx3.googlemail.com
wurmonline.com  MX preference = 40, mail exchanger = aspmx2.googlemail.com
wurmonline.com  MX preference = 70, mail exchanger = aspmx5.googlemail.com
wurmonline.com  MX preference = 30, mail exchanger = alt2.aspmx.l.google.com
wurmonline.com  MX preference = 60, mail exchanger = aspmx4.googlemail.com
wurmonline.com  MX preference = 10, mail exchanger = aspmx.l.google.com
wurmonline.com  MX preference = 20, mail exchanger = alt1.aspmx.l.google.com

(see https://help.mailgun.com/hc/en-us/articles/360011804533-Sender-Verification-Error)

I discovered this when trying to reset my 2FA and and tried a reset password request, which i have since fixed, but the underlying email issue still remains