Hi,
Thanks for looking at this.
SBS 2011 running Exchange 2010.
Issue: External mail stopped at 08:16 this morning!
I tried to Telnet from outside and instead of getting the exchange banner like it always did it now returns "press any key to continue...."
I had a check of the internet and couldn't find anything relevant so thought I would post here.
The MX records have always been set to mail.domain.co.uk pointing to the correct static IP of the SBS box. Previously when a telnet session was started to mail.domain.co.uk 25 it would return with the standard Exchange 2010 banner with the FQDN of remote.domain.co.uk and you could then test sending an email to an internal recipient.
There are other domains for which it is authorised and their MX records are set to mail.domain2.co.uk with the static IP of the SBS box. These also fail if you try to Telnet to them with the same "press any key to continue...."
I can telnet ok to remote.domain.co.uk and it logs in ok and I cam send a test mail.
I've rebooted the Server and applied updates it has found but it still refuses Telnet sessions and obviously other external email.
Internal mail is working OK.
Nothing had changed after 8:16 and I've checked the receive connectors and the look OK.
I've updated the main MX to remote.domain.co.uk and am waiting for that to propagate but would be interested to find out the underlying cause.
Thanks for your help.
Pete