I have a windows 2008 R2 VM running Exchange 2010 std.
Email flow is working perfectly with the exception of verizonwireless.com. They just wont' accept our email. This is the error from the mail queue. I'm so fed up with this. I even called Microsoft and they had no answer. their answer was "It's either your ISP or your Smoothwall". so yesterday I removed the smoothwall from the network and problem still there. ISP, of course, says "nope not us".
any ideas on this?
451 4.4.0 primary target IP address responded with: "554 vanguard.verizonwireless.com." Attempted failover to alternate host, but that did not succeed. Either there are no alternate hosts, or delivery failed to all alternate hosts.