Gmail rejecting Plusnet mail

[#1]

That's what I was after. It does still seem as though gmail doesn't think you have an SPF record!.

Unless you are classed as a bulk sender (>5000/day) to gmail addresses then you should only need either SPF or DKIM authentication.

The FROM and return path in your emails is your domain address ?

[#2]

@Black_Shuck you could try the mxtoolbox deliverability checker https://mxtoolbox.com/deliverability

Never tried it myself but if it does what it says on the tin , then it should give a report including SPF validity

[#3]

Thank you to all that took time out to help me resolve this issue.

The final part of the puzzle to fix the problem was the outgoing server settings, so thank you for posting those.

Again, sincere thanks & appreciation for everyone who spent valuable time sharing their knowledge to help me.

[#4]

@Black_Shuck so what was the issue with the outgoing settings ? was it not using STARTTLS ?

[#5]

Yes, I changed port number & START TLS as advised

[#6]

Thanks, that's useful to know, although I can't quite see why the connection from you to the Plusnet servers, when submitting the email, should be of any concern to gmail but I guess that's google for you!