I know almost nothing about Exchange or outlook behind the GUI. Our outsourced IT has recently upgraded our exchange server to 2010, and now we are experiancing a number of problems with external addresses. (POP,SMTP)
Could you give me some suggestions to pass on to our External IT as to where to look as to why my automated SMTP send that worked perfectly with the last verion of the Exchange Server is no longer working with the upgraded version 2010?
All automated SMTP emails that I send to internal addresses only works fine. But anything that contains ANY external email addresses fails for all recipents, 550 unable to relay. I had been using mymail.co.com as the SMTP server, and I am using authentication.
I'm assuming the authentication must still be valid or nothing would get through.