Windows10 Issues with ProxySG

[Rigels Sino]

Hello all,

I am looking for some suggestions regarding an issue I am coming upon.
Proxy Deployment Mode is Explicit Mode, and proxy settings are pushed via GPO.
When using the Exchange Server configuration on Microsoft Outlook via Auto-Discovery the synchronization to the Mail server simply drops and then the software closes. Upon re-opening there is an error that some settings didn`t get collected.
I have seen that this issue occurs only on Windows 10, tested couple Windows 7 and the process is ok without any issues.

Any suggestions please?
This is urgent case.

Thanks,
Rigels

[Jacob Miles]

Hi Rigels,

Do you have a screenshot of the error that you get on reopening?

[Rigels Sino]

Hello Jacob,

Sorry for the late response.Attached to this reply will be Windows 7 Screenshots(Successful AutoDiscovery) and Windows 10 Screenshots(Unsuccessful AutoDiscovery.)I will also attach Wireshark captures of the process for both Windows 7 and 10.

Thank You,
Rigels Sino

Attachment(s)

Windows 10 Outlook Auto Discovery - Unsuccessful.rar   1.43 MB 1 version

Windows 7 Outlook Auto Discovery - Successful.rar   173 KB 1 version

[Jacob Miles]

Hi Rigels,

From the packet capture, in stream 9, your client machine is asking for the autodiscover.xml file going transparently instead of explicitly, and is getting met with a 403-forbidden from the Microsoft server (see the server header of the 403). I don't see any indication that the ProxySG is meddling in anything from the packet capture (or that the affected traffic is going to the ProxySG at all), but you could always take a packet capture off the ProxySG itself to verify whether the autodiscover traffic is traversing there, and if it is, try the below troubleshooting code to test whether the ProxySG is interfering if you have any doubts. 

https://knowledge.broadcom.com/external/article?legacyId=tech243229

A lot of times I see a certificate error of some sort with autodiscovery when it fails, but we don't see that here. In addition to the packet capture, the error you are getting states "The Microsoft Exchange information service in your profile is missing required information", which to me, would indicate a configuration issue, and not so much a network issue. Given that this appears to be OS specific, that would further my belief in a configuration issue.

At this point, the issue does not appear to be network related, and so I would reach out to Microsoft for further support on the issue.

Thanks!

[Rigels Sino]

Hello Jacob,

Sorry for the late response have been working on Multiple projects this week.
What you said is pretty correct as I also came across the same conclusion after Sniffing the traffic with Wireshark and analyzing it.
We have scheduled with the Systems Department the Upgrade of the Microsoft Exchange in order to fix some issues with it and also implement a new Certificate.
Upon that I will test the packet capture you suggested.

Thanks again and I will get back to you with an answer,
Yours,
Rigels Sino

[Spooky Porpoise]

Thanks for the information.

[Rigels Sino]

Hey Jacob,

I have fixed the issue some time ago but haven`t been able to give a feedback for anyone else having the same issue.
The problem was actualyl related to the Systems Team, yet I had to come across a solution.
The issue was with the IE/Chrome/Firefox Automatically Detect Settings as no matter what after each restart it would be ticked, taking priority over the manually configured settings pushed via GPO.

If anyone has the same issue please have a look at the Registry that i found out and pushed via GPO to always disable the Automatically Detect Settings, also make sure to make the Proxy Options Settings unselectable via ADMX Templates on Chrome and Firefox if it is a Strict Client.

Thanks again,
Rigels Sino

[Jacob Miles]

Thanks for the update Rigels!