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    Office 365 SMTP server not advertising StartTLS

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    • wrx7mW
      wrx7m @flaxking
      last edited by

      @flaxking said in Office 365 SMTP server not advertising StartTLS:

      @wrx7m said in Office 365 SMTP server not advertising StartTLS:

      Could it be TLS 1.2 is not set as the default on the client system? If it is Windows 7, you need to adjust some registry entries.

      The one email library will only use a maximum of TLS 1.0. And it is before the TLS handshake, so I wouldn't think that TLS version would be a consideration yet.

      OK, because they started forcing TLS 1.2 back in October.

      F 1 Reply Last reply Reply Quote 0
      • F
        flaxking @wrx7m
        last edited by

        @wrx7m said in Office 365 SMTP server not advertising StartTLS:

        @flaxking said in Office 365 SMTP server not advertising StartTLS:

        @wrx7m said in Office 365 SMTP server not advertising StartTLS:

        Could it be TLS 1.2 is not set as the default on the client system? If it is Windows 7, you need to adjust some registry entries.

        The one email library will only use a maximum of TLS 1.0. And it is before the TLS handshake, so I wouldn't think that TLS version would be a consideration yet.

        OK, because they started forcing TLS 1.2 back in October.

        Nope, they've updated that notice

        wrx7mW 1 Reply Last reply Reply Quote 0
        • wrx7mW
          wrx7m @flaxking
          last edited by

          @flaxking Guess we are thinking of different notices... https://support.microsoft.com/en-us/help/4057306/preparing-for-tls-1-2-in-office-365

          F 1 Reply Last reply Reply Quote 0
          • F
            flaxking @wrx7m
            last edited by

            @wrx7m "Note This doesn't mean Office 365 will block TLS 1.0 and 1.1 connections. There is no official date for disabling or removing TLS 1.0 and 1.1 in the TLS service for customer connections."

            wrx7mW 1 Reply Last reply Reply Quote 0
            • wrx7mW
              wrx7m @flaxking
              last edited by

              @flaxking Gotcha. But, it has caused issues depending on how you are connecting and what you are connecting with. I had issues connecting with Windows 7 and Outlook and was told by support to apply registry fix and make sure a certain update was applied.

              1 Reply Last reply Reply Quote 0
              • DashrenderD
                Dashrender
                last edited by

                Isn't the list of SMTP commands given before there is any attempt to bring up a TLS tunnel? Assuming my understanding of that is correct - then it shouldn't matter what version of TLS is supported - the advertising of STARTTLS should still be in the list - and the library's aren't seeing them - right?

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                • F
                  flaxking
                  last edited by

                  From what I heard from our tech, it sounds like the company's UTM was messing with it.

                  scottalanmillerS dbeatoD 2 Replies Last reply Reply Quote 0
                  • scottalanmillerS
                    scottalanmiller @flaxking
                    last edited by

                    @flaxking said in Office 365 SMTP server not advertising StartTLS:

                    From what I heard from our tech, it sounds like the company's UTM was messing with it.

                    That's quite possible. UTMs can introduce a lot of problems.

                    DashrenderD 1 Reply Last reply Reply Quote 0
                    • DashrenderD
                      Dashrender @scottalanmiller
                      last edited by

                      @scottalanmiller said in Office 365 SMTP server not advertising StartTLS:

                      @flaxking said in Office 365 SMTP server not advertising StartTLS:

                      From what I heard from our tech, it sounds like the company's UTM was messing with it.

                      That's quite possible. UTMs can introduce a lot of problems.

                      LOL I was going to say the same thing...

                      1 Reply Last reply Reply Quote 0
                      • dbeatoD
                        dbeato @flaxking
                        last edited by

                        @flaxking said in Office 365 SMTP server not advertising StartTLS:

                        From what I heard from our tech, it sounds like the company's UTM was messing with it.

                        Which UTM? Hopefully not SOnicwall in this case.

                        scottalanmillerS 1 Reply Last reply Reply Quote 0
                        • scottalanmillerS
                          scottalanmiller @dbeato
                          last edited by

                          @dbeato said in Office 365 SMTP server not advertising StartTLS:

                          @flaxking said in Office 365 SMTP server not advertising StartTLS:

                          From what I heard from our tech, it sounds like the company's UTM was messing with it.

                          Which UTM? Hopefully not SOnicwall in this case.

                          Hopefully it IS SonicWall, so that all these stupid issues can be isolated to one bad vendor rather than sprawling across the industry.

                          dbeatoD 1 Reply Last reply Reply Quote 1
                          • dbeatoD
                            dbeato @scottalanmiller
                            last edited by

                            @scottalanmiller said in Office 365 SMTP server not advertising StartTLS:

                            @dbeato said in Office 365 SMTP server not advertising StartTLS:

                            @flaxking said in Office 365 SMTP server not advertising StartTLS:

                            From what I heard from our tech, it sounds like the company's UTM was messing with it.

                            Which UTM? Hopefully not SOnicwall in this case.

                            Hopefully it IS SonicWall, so that all these stupid issues can be isolated to one bad vendor rather than sprawling across the industry.

                            They are not the only one as I can mention many....

                            1 Reply Last reply Reply Quote 0
                            • F
                              flaxking
                              last edited by

                              No idea, we don't manage the client's infrastructure

                              StrongBadS 1 Reply Last reply Reply Quote 0
                              • StrongBadS
                                StrongBad @flaxking
                                last edited by

                                @flaxking said in Office 365 SMTP server not advertising StartTLS:

                                No idea, we don't manage the client's infrastructure

                                Then it was definitely the UTM, no question.

                                1 Reply Last reply Reply Quote 0
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