We have a client who cannot send us emails but we can send to them. Even when they reply to our sent emails they get a bounce back. Here is the error. Name@ourdomain.co.uk 5.1.3 SMTP; 553 Request action not taken: Mailbox name not allowed or chunk too large
I saw in another problem on here somewhere that "chunk too large" is a Watchgaurd firewall message. Now the thing is that we have a watchgaurd firewall. How do I fix this. It is only one domain that cannot send to us so dont really want to turn off our firewall.
