Problem Connecting After Moving Server | MDaemon Technologies, Ltd.

Problem Connecting After Moving Server


  • Server 2022 VMware vm / MDaemon 23

    I moved my MDaemon installation to a new server following the instructions I found online and everything appears to be working from the outside.  However, Outlook on the LAN is producing a (0x800CCC0E) error.  I made sure MDaemon.exe and Worldclient.exe are allowed in the firewallI with no change.  I also temporarily disabled the firewall and still no mail can be sent or retrieved from the LAN through the gateway.  DNS is translating the address correctly.  Tcpview does show MDaemon listening on the correct external ip address.  Any suggestions for troubleshooting this would be appreciated?

    Thanks,

    jay



  • You mention that TCPview shows MDaemon listening on the correct external IP address, is it also listening on a local IP address? 

    On the Outlook machines, is DNS pointing the hostname to the local or the external IP address?  It should be pointing to the LAN address from the LAN.  If its pointing to the external address, your firewall is probably blocking the traffic.

    What do the MDaemon logs show is happening?

    What ports is Outlook configured to use?

    What ports is MDaemon listening on for IMAP and SMTP?

    On the MDaemon server open a command prompt running as an administrator and run the following

    telnet $LOCALIP$ $PORT$

    Where $LOCALIP$ is the local IP address of the MDaemon machine(not 127.0.0.1), and $PORT$ is the port that Outlook is trying to use.

    you should get a response back.

    Then try the same thing on one of the machine where Outlook is running and cannot connect. What type of response do you get?


  • Thanks for the response, Aaron.

    MDaemon is using the standard ssl ports, 993 & 465

    What's strange is, if I shut the new server down and start up the one I moved from it works perfectly, as always.  Both are set to use mail.domain.com for both incoming and outgoing mail.  The LAN computers (Laptops) use the same Comcast Business DNS so they are all going through the gateway (router on the LAN) and Outlook is looking for mail.domain.com which translates correctly on every computer on the LAN. I have it setup this way because the laptops often are out in the field on wifi somehwere.   It is strange that mail works for the original server, but not for the new one where the settings have not changed. 

    When looking at Tcpview on the original server it shows an established connection for IMAP and SMTP on the correct external ip address of the server from the correct ip address from the router on the LAN .  When I shut that server down the old, working server, and power up the new server Tcpview shows established connections from only outside of the router.  The external router ip address never appears.  That must mean the external ip address of the router is being blocked somehow by the new server.  It can't be the router because this all works with the old server.  Where would I look to see if the new server is blocking the routers ip?  BTW, I get no response from either server using Telnet.


  • If you are not getting a response from Telnet, the something in between the client and server is blocking it.  Since Outlook works when using the old server, I'd guess that whatever it is is detecting that it is a manual connection and blocking it.  

    Did you configure MDaemon on the new machine to use the correct certificates?  If you didn't change the certificate configurations in MDaemon then you'll need to copy the certificates from the old machine and install them on the new machine in the same location in the certifcate store.  Or if you have new certificates on the new machine, then just configure MDaemon, webmail, and Remote Administration to use the new certificate.

     


  • The Let's Encrypt certificate is gone on the new server and when I try to run Let's Encrypt nothing happens.  Is there a way to force Let's Encrypt to run and create a new certificate?


  • What does the LetsEncrypt log show is happening?  It can be found in the MDaemon\Logs directory.

    If you have webmail configured to redirect HTTP to HTTPS and there is no HTTPS certificate, the redirection will fail when attempting to complete the HTTP challenge and LetsEncrypt will not issue a certificate.  Try turning on HTTP and HTTPS, then run LetsEncrypt.  Assuming that works, you can then re-enable the option to redirect HTTP to HTTPS.


  • The Let's Encrypt log showed a 400 error and suggested a firewall problem.  I disabled the firewall and Let's Encrypt ran and created a certificate successfully.  Outlook also successfully connected and retrieved mail.  I enabled the firewall and Outlook failed. MDaemon.exe and Worldclient.exe are set to "Allowed" in the firewall list of programs.  What am I missing?


  • I was wrong.  MDaemon.exe and Worldclient.exe were both gone from the firewall "Allow" list.  I added them back and the new server is working perfectly now.  Thank you! for your help, Aaron.

    Jay


  • I am not well versed in the Windows firewall, but its gotten me a few times...

    When you turn the Windows firewall on, there are settings to block all incoming connections including those in the list of allowed apps, do you have that enabled.

    When the mdaemon.exe and worldclient.exe are set to allowed, are they allowed for private or public networks.  Is the current network setup as private or public?

    If you go to the advanced settings, Monitoring / Firewall, do it show the connections being blocked?

     

     

     


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