Unable to on outlook after connecting Open VPN



  • Hello Everyone,

    Last couple of days we are facing some issues with PfSense. When we connect a user from a remote location via Open VPN then after connecting VPN everything is working fine. but we are unable to connect outlook only after connecting Open VPN and getting below error. are disconnected VPN outlook is working fine.

    RightNow we are using office365 for mailing services.

    Error - We are unable to connect right now. Please check your network and try again later
    Firewal IPS Version - 2.3.5-RELEASE (amd64)


  • LAYER 8 Global Moderator

    For starters pfsense 2.3.5 has been EOL for quite some time.. Update to current if you want any sort of help.

    Oct 31 will be a YEAR since it was eol, and there was even a year before that warning that it was going to be no longer supported.. And your not even running the latest version of that p2? Why should anyone waste any time helping someone that can't even keep their firewall even somewhat current?

    Not meaning to rant at you specifically, but this is just nonsense to be running such an old version of your FIREWALL.. meant to protect your network, etc..

    Does MS support windows 98 still? ;)



  • Hello Everyone,

    Please suggest for the same and let us know why we are getting such types of issue.



  • @shiv_znet said in Unable to on outlook after connecting Open VPN:

    to connect outlook

    @shiv_znet said in Unable to on outlook after connecting Open VPN:

    we are using office365 for mailing services.

    Sorry, I don't know all Microsoft mail services.
    So, please detail : are you using Office 365 Outlook, the fat mail client ? A web-mail service ?
    What URLs, ports, protocols ?

    @shiv_znet said in Unable to on outlook after connecting Open VPN:

    Error - We are unable to connect right now. Please check your network and try again later

    The error states, that you can't connect to ... where ever you want to connect to.
    Your are connected as a client to pfSense using the OpenVPN server, right ?
    What are the firewall rules on the OpenVPN interface tab ?

    Btw : your pfSense didn't change lately. I guess it didn't change for the last year or two. So, if there are issues, it must be the settings.
    So, tell us, what (did you) change ?


  • LAYER 8 Netgate

    Regarding the known issue of Microsoft Office products failing to work on Windows 10 with OpenVPN, the root cause appears to be that the Network Location Awareness (NLA) and Network Connection Status Indicator (NCSI) services will not function without a default gateway set for the OpenVPN interface.

    The workaround illustrated in this blog post appears to work as advertised.

    For additional support with this specific issue, please see https://support.microsoft.com/en-us.

    It is not possible to resolve the issue from the pfSense side and this is strictly a Microsoft issue. It will require Microsoft addressing the underlying behavior of their software before this workaround will no longer be needed.


  • LAYER 8 Netgate

    It is not pfSense or OpenVPN. It is Windows.



  • Furthermore : the solution talks about a TAP OpenVPN solution.
    TAP : that's pretty like your asking for troubles.

    Anyway, I'm using Office 365 myself @ home.
    It happens rather often that I'm connected to work, using the OpenVPN client delivered by pfSense, connected to the OpenVPN server exposed by pfSense.
    Everything works well. Maybe I don't have any issues because : I'm using TUN and IPv6 over VPN ....


  • LAYER 8 Netgate

    Up to Microsoft to solve. There is nothing wrong with the OpenVPN /1 "default" route solution. In fact, it's pretty simple and elegant. As I understand it, Microsoft has hard-set something to do with the 0.0.0.0/0 route on the workstation which is just dumb. This is up to them to fix. That is where any torches and pitchforks should be taken.



  • Hello Everyone,

    Today we observed that when we are using updated version - 16.0.11328.20420 of Microsoft outlook then getting this error.

    When we use the lower outlook version then all things are working.

    Please suggest what can we do????



  • @shiv_znet said in Unable to on outlook after connecting Open VPN:

    Please suggest what can we do????

    Stop using Outlook! 😉



  • ... or take the OpenVPN using the horrible TAP out of the equitation.


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