Forward Error PRX5
Question / Problem
What can I do if the Exchange Server responds: "451 4.7.0 Temporary server error. Please try again later. PRX5"?
Answer / Solution
This error results of invalid DNS settings. To solve it add the local server's IP to our hosts file (C:\Windows\System32\drivers\etc\hosts):
192.168.1.5 server
192.168.1.5 server.domain.local
Then restart "Microsoft Frontend Transport" and "Microsoft Exchange Transport" services.