BTINTERNET mail server won't accept mail from our mail server

[tinkerg]

We run a mail server locally which of course sends mail to many of our clients and suppliers.

However a number of our users are reporting an inability to send to btinternet email addresses.

Our mail server logs show that the btinternet mail server is dropping the connection.

Is there any extra security that bt is applying to its mail servers that we need to be aware of.

[nicholashowson]

Dear BT

I have an email address that I carried over from my BT account.  I need to go into it but I cannot.  I have urgent emails that need answering.  Please help.

Nicholas Howson

[nicholashowson]

How can I get onto my email address: <nicholashowson@btinternet.com>.