Cannot e-mail from btinternet.com to user in particular domain - consistently getting error 451

[sparker1967]

Whenever I try to mail from my btinternet.com mail account to a friend with an account hosted in the @rwframing.co.uk domain, I get the following  message: "Diagnostic-Code: smtp; 451 Temporarily unable to process your email. Please try again later.".

My friend successfully receives e-mails if I send them from my @gmail.com account and from anyone else who doesn't use btinternet.com, but does not receive anything from anyone who mails from btinternet.com.

I assume there's nothing that I can change whilst composing or sending my mail to resolve this and there is an issue between the btinternet.com and rwframing.co.uk mail servers. Is there anyone on this forum that can investigate, please?

[gg30340]

Your friend would need to get it checked by his domain if they are the ones blocking BT emails.

[sparker1967]

My friend has already taken this up with her provider. They said they could see no reason and suggested asking the BT internet customer (me) to take it up with BT.

[gg30340]

If your friend is not receiving emails as you have stated from anyone, not just you,  who sends to him using a BT email account it is very unlikely that BT is the problem. It would appear that your friend's domain is blocking BT emails.

How are you sending your email, is it with an email client/app or are you using webmail on a web browser?

If using an email client/app try sending an email by logging onto your email account using a web browser.