Hi All,
I am trying to send a mail from my xxx@hispeed.ch account to a large company - I am getting the following error:
SMTP error from remote mail server after RCPT TO:<removed>:
550 SPF Sender Invalid - envelope rejected - https://community.mimecast.com/docs/DOC-1369#550 [i8XPWwrXMZGWCDz3XnZ7vg.uk114]
If I analyze the email header, I see this
I think this is a sunrise / UPC issue - not something I have any control over.
Any ideas how to solve this?
Thnaks
Will