In the original thread posted to here, Solved: Server Error 421 Can't Send Emails - Virgin Media Community - 4848415, the issue was:
Server Error: 421
Server Response: 421 csmtp5.tb.ukmail.iss.as9413.net cmsmtp Virgin Media has blocked your connecting IP xx.xx.xxx.xx Too many bad emails have been sent.
If you are seeing the same then go to https://netreport.virginmedia.com/netreport/ and:
- select an abuse type of Email Sending Errors from drop down list
- select an abuse form of Other from drop down list
- paste the error message shown in the curl command output but not the command itself into the Log Evidence area
- enter your name into My name field
- enter your email address into Email address field
- select Submit button
Should de-listing not occur then post back here to have the forum team investigate further; until then use webmail.
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