email send - error 552

[#1]

I am trying to forward an email from Equiniti / ShareView "Lloyds Banking Group plc - Availability of Annual Report and Accounts and Notice of Annual General Meeting".
It is failing to send with the message "552 bZTD1s0074TittM01ZTKck message rejected due to spam or virus. If you believe this is in error please login to your portal or contact your ISP support team."
1. I checked the email header and body so far as I can
2. It is an email I was expecting
3. There are no virus alerts from my other threat detection tools.
Please can someone take a look at this at your earliest convenience.
Thanks
David

[#2]

Have you tried to "forward as an attachment" instead?

[#3]

Good idea.
Tried it and it still failed but with a different 'virus' sig:
"552 bsEk1s00G4TittM01sEmHF message rejected due to spam or virus"

[#4]

Just had a chat session with customer service. They were not sure what is happening but recommended me to drop the spam filter in email settings. I thought that was only for inbound email but I'll try it and see what happens. It can take up to 48 hrs to take effect so I'll be back in a bit.
Edit: and I've identified the bit of the message that causes the exception, it is http://www.lloydsbankinggroupagm.com and that URL is genuine.

[#5]

You are right that the Member Centre spam filter settings affect only incoming emails; nothing within our direct control has any influence on the behaviour of the filter on outgoing messages.
I believe Customer Services need to be involved with retraining the spam filter but that will probably involve a ticket being raised via chat.