This problem really has me stumped. Any help would be much appreciated. Exchange 2007 is installed and clients connect using Outlook 2007. There are also IMAP clients who access the server successfully. POP3 is enabled and I have confirmed the users are authorized to access the server. The server requires a secure connection. Netstat confirms that the server is listening on port 995 (IMAP port 993 works fine). However, when a client tries to login to the POP3 server, they get a "server unavailable." Full message is: There was a problem logging onto your mail server. Your Password was rejected. Account: 'Lunaguitars', Server: 'mail.lunaguitars.com', Protocol: POP3, Server Response: '-ERR Server Unavailable. 21', Port: 995, Secure(SSL): Yes, Server Error: 0x800CCC90, Error Number: 0x800CCC92 The POP3 log on the server is enabled. It shows the following while attempting a connection from within the network. A connection outside the network gets the same error (firewall is open for necessary port 995). Microsoft Exchange Server 2007 POP3 service ready,2007-06-14T01:24:45.359Z,,0000000001C9D1A8,2,192.168.1.200:995,xxx.xxx.xxx.xxx:2754,<,USER Pronetserv@dean.lcl,2007-06-14T01:24:45.359Z,,0000000001C9D1A8,3,192.168.1.200:995,xxx.xxx.xxx.xxx:2754,>,+OK,2007-06-14T01:24:45.390Z,,0000000001C9D1A8,4,192.168.1.200:995,xxx.xxx.xxx.xxx:2754,<,PASS ***********,2007-06-14T01:24:45.406Z,,0000000001C9D1A8,5,192.168.1.200:995,xxx.xxx.xxx.xxx:2754,*,,"User Pronetserv Server name DNCEX.dean.lcl, version1912636077, legacyId /o=XYZ Organization/ou=Exchange Administrative Group (FYDIBOHF23SPDLT)/cn=Recipients/cn=Pronetserv"2007-06-14T01:24:45.421Z,,0000000001C9D1A8,6,192.168.1.200:995,xxx.xxx.xxx.xxx:2754,>,-ERR Server Unavailable. 21,2007-06-14T01:24:45.421Z,,0000000001C9D1A8,7,192.168.1.200:995,xxx.xxx.xxx.xxx:2754,>,-ERR Connection is closed. 22,2007-06-14T01:24:45.421Z,,0000000001C9D1A8,8,192.168.1.200:995,xxx.xxx.xxx.xxx:2754,-,,Local I have read everything on the subject and nothing comes close to explaining what is happening. The get-popsettings look good and I will post them if someone thinks they can help me. Tony tlombardi@nospam.pro-netserv.com remove nospam. for email address.

Having the *exact* same problem. We don't usually use POP3 but an automated account on one of our apps does. Funny thing is that I can connect to the mailbox through POP3 on Exchange 2007 to the mailbox on an Exchange 2000 server....but as soon as I try to connect to a mailbox on an Exchange 2007 server it stops working. Surely there's gotta be someone out there who knows how to fix this?