At my current client they are using POP3 and we are in the process of setting up Exchange 2013 servers to act as hybrid servers for their Office 365 migration.
So after setting up the servers I tested all protocols, then a day or so later I noticed that POP3 was showing down on the Kemp NLB. When I did TELNET test to port 110, from a remote machine, using the FQDN or IP the connection was dropped after a few moments, without returning any text.
I then tried from the Exchange server [2013 CU5, multi-role, 2 NICs (iSCSI and Pubic), POP bindings 0.0.0.0] itself and had the same results. I then tried 127.0.0.1 and localhost with TELNET and those worked. So the service was working, but not as expected.
I tried rebooting and resetting several settings on the PopSettings and searching for this issue on-line, but came up empty. So finally went to the TechNet Exchange Server 2013 – Outlook, OWA, POP, and IMAP Clients forum and searched on “pop connection” and found this post: POP works via localhost but not from other networked machines, which included the “fix.”
The issue was that the “State” of the PopProxy component was set to Inactive:
[PS] D:\>Get-ServerComponentstate -Identity SRVDENEX01
Server Component State
—— ——— —–
SRVDENEX01.company.com ServerWideOffline Active
SRVDENEX01.company.com HubTransport Active
SRVDENEX01.company.com FrontendTransport Active
SRVDENEX01.company.com Monitoring Active
SRVDENEX01.company.com RecoveryActionsEnabled Active
SRVDENEX01.company.com AutoDiscoverProxy Active
SRVDENEX01.company.com ActiveSyncProxy Active
SRVDENEX01.company.com EcpProxy Active
SRVDENEX01.company.com EwsProxy Active
SRVDENEX01.company.com ImapProxy Active
SRVDENEX01.company.com OabProxy Active
SRVDENEX01.company.com OwaProxy Active
SRVDENEX01.company.com PopProxy Inactive
SRVDENEX01.company.com PushNotificationsProxy Active
SRVDENEX01.company.com RpsProxy Active
SRVDENEX01.company.com RwsProxy Active
SRVDENEX01.company.com RpcProxy Active
SRVDENEX01.company.com UMCallRouter Active
SRVDENEX01.company.com XropProxy Active
SRVDENEX01.company.com HttpProxyAvailabilityGroup Active
SRVDENEX01.company.com ForwardSyncDaemon Active
SRVDENEX01.company.com ProvisioningRps Active
SRVDENEX01.company.com MapiProxy Active
SRVDENEX01.company.com EdgeTransport Active
SRVDENEX01.company.com HighAvailability Active
SRVDENEX01.company.com SharedCache Active
A quick call to Set-ServerComponentState to mark this component Active fixed the issue:
Set-ServerComponentState -Identity SRVDENEX01 -Component PopProxy -Requester HealthAPI -State Active
After doing this POP started responding as expected, using any valid hostname or IP address.
Like the user who posted to TechNet, I would also like to know why the health check failed and marked the PopProxy as inactive. I will research this further and if I find anything I will update this post.
Jason (Izzy) Sherry's Blog 
I have been having the EXACT SAME issue! I have 2 servers in a cluster, and one of the two (always the same one) dies by going inactive by the HealthAPI. I have to force it back up all the time. No clear reason why. If you find anything, I would appreciate the help, as i’ve been tearing my hair out trying to figure out this one.
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Thank you a lot for sharing this info. Saved me hours debugging
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Pingback: Fixed POP3 Service after Exchange 2013 CU6 broke it | jermsmit.com
Hey Thank you so much Jason, you saved me some time in waiting for Microsoft product support.
I have just finished dealing with them over a replication issue caused by CU6. This issue happened to us right after our CU6 upgrade which we were instructed to due to address a Hybrid issue
I gave you credit for this in my blog post: http://jermsmit.com/fixed-pop3-service-after-exchange-2013-cu6/
Once again, thank you
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Have you found the cause of its failure yet?
We have this popproxy failing each day at random hours, not able to find a cause?
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No, this was for a client that used POP3. Once we fixed the setting with Set-ServerComponentState the issue didn’t come back up.
Open a ticket with support\PSS and they will track it down and it won’t cost you anything; your money or issue use will be refunded.
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Thank you. Very helpfull info. I had the same issue.
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Thank you very much for this valuable information
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This solved the login to pop but now the smtp fails. Oddly I have a vpn and use the same settings 587 tls and it works from my desktop from from anywhere outside the send test fails. I definitely have port 587 open on the firewall.
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This post is about POP3, 587 is (normally) used by SMTP. In any case, a blog isn’t a good support form. If you post your issue on the TechNet forums you have a much better chance to get help there.
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Thank you very much! This fixed my issue with the ImapProxy component. Thanks again!
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You saved my day with this one! We are running a clean installation of Exchange 2013 CU6, the problem occurred after we installed KB3011140 for Exchange 2013 CU6. As soon as we ran the command from your post, POP started to work again.
Another error that might point to the problem described is if you encounter this (multiple times) in the pop3 logging:
127.0.0.1:995,127.0.0.1:37195,,1,0,31,CloseSession,, (maybe add it to your blogpost?)
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I don’t see an error in that log entry. Just looks like connection info, unless the last “1,0,31” part is an error code.
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I ran into exactly this problem. I have nearly pulled out all hairs on top of my head to solve this problem. The problem started here after I upgraded the Exchange certificate. I may have deleted the old one in the wrong order or so. But Jason, you’ve saved my day. POP3 and IMAP (which had the same problem) are now working again.
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Thanks Jason, was causing us problems and your post helped greatly.
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Thank you for this post, this solved my problem
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So all of these components should be active? I still have 3 more that are inactive. BTW this corrected my issue, thanks!
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Thank you a lot for sharing this very useful info! I lost my weekend ….
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Thanks Jason after 3.5 days trying to fix my POP3 connection I found this post and now it is all ok.
You saved me just in time for a customer demo tomorrow 🙂
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We have CU7 here and the issue stil occurs. I’m sitting here waiting Microsoft to fix that….
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In our case, editing the server settings corrected the component issue. Make sure that POP3 and IMAP4 have (All available IPv6) and IPv4 listed instead of the servers actual IP. This goes for both the TLS and SSL connection settings. Once I put this back in place the components stopped going offline.
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Hi Brian, ipv4 settings are configured for the server’s actual IP for 995. Changed it to “all available ipv4”. Let’s see…
Thanks for the tip.
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Fixes out problem after a netwerk broadcast storm.
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I did run commands as Jasons Herry suggested but POP3 and POP3backend services failed to start. The commands that I run as follows:
Get-ServerComponentstate -Identity Servername
Set-ServerComponentState -Identity Servername -Component PopProxy -Requester HealthAPI -State Active
Any idea?
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we are using pop3 for some voicemail boxes of a broadsoft voip solution, and someday pop3 just stopped working… because of 0 logging but for this error:
after: The service has started successfully. PID 12100 EVENTID 1001
there came this: The POP3 server’s Online status has changed to False. EVENTID 1011
i looked hours for a solution ,because eventlog was full of errors regarding perfcounters i looked there first but could find anything: thanks a lot for this !
i guess this came from too many connections on port 110 …
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Hi,
Thanks a lot i was searching the related issues, all over..
You saved the day of mine.. anyway i copy the error msg i got from pop clients. it will help full for other who doing google.
Unable to send or receive messages for the xx account. Your server has unexpectedly terminated the connection. Possible causes for this include server problems, network problems, or a long period of inactivity. Server: ‘POPServer’ Windows Live Mail Error ID: 0x800CCC0F Protocol: POP3 Port: 995 Secure(SSL): Yes
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It seems that the Hybrid Configuration with Office 365 is the responsible for that. In my case it was.
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You saved my life 🙂 ! BIG THANK YOU!
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My name is Felipe from Brazil. Thank you for the post. Same problem fixed in my company.
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THANK YOU!!!!
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THANKS!
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Thank you! I had a same problem after installing Exchange 2013 CU13.
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From Morocco.
Great post; thanks !!!!
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Thanks very much. Scratching my head after an hour or so and found this post. Was pretty much out of ideas after restarting the POP services on both CAS and MBX servers.
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Thanks. exact same problem, you solved it with your post. thanks Thomas
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Your knowledge has been a great help to me.
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Thank you so much for this! I spent hours trying to figure out what was causing the issue with one of our internal applications failing to send out emails – this worked a treat!
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After a couple of Windows updates the PopProxy property went to inactive, then after 5 min. of googling, problem fixed!
Thank you.
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Really appreciate this post!!! was exactly the issue i was facing
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Thank you So much , Great Article and fix for our Exch 2013 issue
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This happens once a year and I always have to rack my brain. Good thing the google search always brings me back here for the quick fix.
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Thank you very much! Solved the same problem !
kiss kiss kiss !
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And almost 4 years later this article is still saving people…like me! Thanks for posting!
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Thank you very much, this made my day!
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I’m throwing in a ‘Thank You!’ Same issue as others, had my ticketing system notification stop due to this error. I went through all the normal steps and found Exchange no listening on POP ports. Now time to track down ‘why’.
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Thank you!
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Pingback: Exchange 2013 POP connections are failing and service is running | Bart Vincke's Blog
Thank you very much. You are a life saver. 😀
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The crazy thing here is after 5 years, nobody has ever been able to come with with the “WHY”. Its been a ton of CU fixes, and this stupid problem still is happening.
Has anyone been able to come up with a WHY here???
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Thanks for the blog. It work exactly as you detail.
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sheesh, we had the same issue and spent about 1 hour trying to figure it out. Now it is fixed, thank you very much my friend.
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Thank you SO much. I still tend to check the GUI to find issues (silly me. That WAS windows claim to fame right). Finally found your post and checked the management console. There they were…….inactive
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Thank you! After hours of poking about on a system that had been working and suddenly not… This solution got me back in business!
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and still this is happening. thank you! found your post from here: https://community.spiceworks.com/topic/696784-exchange-2013-pop3-failing-it-used-to-work
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Thanks so much!, I spent hours trying to figure out what was wrong with the pop service.
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Thanks a lot! Searching for hours why POP and IMAP does not run. Read your post, done in 5 minutes.
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