Outlook 2019 wont connect to Exchange Server via the WAN

Neil Jones 21 Reputation points
2021-02-14T09:20:35.933+00:00

Cannot connect outlook 2019 to Exchange Server via the LAN or WAN.

I do have a good understanding of Exchange but this one is odd. The Exchange works fine but these two below errors are causing the issue. I just cannot connect outlook. It accepts the user name and password connecting using Auto discovery but just will not complete the final stage and says cannot contact outlook. There must be a certificate issue or DNS problem however this is only happening for a newly connected outlook to exchange server.
One thing i have noticed is when i do a SRV Lookup using MXToolbox its says DNS Record Published DNS Record not found. Would this prevent me from connecting to Outlook.
I'm guessing this is an advanced issue and the person that could only answer this is an advanced Exchange technical person.
Please help

Event 2004
Unable to find the certificate with thumbprint 474EA690EA7D53AC565309AEC2C715C96A87B5B2 in the current computer or the certificate is missing private key. The certificate is needed to sign the outgoing token.

Event 1009

The indexing of mailbox database Mailbox Database 1870481387 encountered an unexpected exception. Error details: Microsoft.Exchange.Search.Core.Abstraction.OperationFailedException: The component operation has failed. ---> Microsoft.Exchange.Search.Core.Abstraction.CatalogReseedException: Some of the notifications for database '9db666cb-c07d-451c-86f7-3244e772c684 (Mailbox Database 1870481387)' are missing. Requesting a reseed.
at Microsoft.Exchange.Search.Engine.SearchFeedingController.DetermineFeederStateAndStartFeeders()
at Microsoft.Exchange.Search.Engine.SearchFeedingController.InternalExecutionStart()
at Microsoft.Exchange.Search.Core.Common.Executable.InternalExecutionStart(Object state)
--- End of inner exception stack trace ---
at Microsoft.Exchange.Search.Core.Common.Executable.EndExecute(IAsyncResult asyncResult)
at Microsoft.Exchange.Search.Engine.SearchRootController.ExecuteComplete(IAsyncResult asyncResult)

Exchange | Exchange Server | Management
0 comments No comments
{count} votes

Accepted answer
  1. Joy Zhang-MSFT 1,051 Reputation points
    2021-02-15T03:03:33.4+00:00

    Hi @Neil Jones ,

    What is the version of your exchange server? How many users are facing this issue?

    Based on the event log 2004, I have done some research, most of them are talking about OWA issue not outlook connectivity issue.
    Could you get returned certificate via running command Get-ExchangeCertificate -Thumbprint 0271xxxxxxxxxxE044F968F068B14B8 | Format-List?
    If you cannot find the certificate, you could have a try to follow these steps in the blog to recreate a certificate to authenticate and then check if this issue continues.
    Please Note: Since the web site is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.

    About event log 1009, you can safely ignore these logged events, which is mentioned in the article: 1009 errors flood Application log for lagged database copies in Exchange Server 2016

    For further troubleshooting, you could run EXRCA to test outlook connectivity and you will get more details.


    If an Answer is helpful, please click "Accept Answer" and upvote it.
    Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.

    0 comments No comments

2 additional answers

Sort by: Most helpful
  1. Neil Jones 21 Reputation points
    2021-02-16T05:33:55.557+00:00

    Hi Zoy Thanks for the reply.

    I am using exchange 2013

    The odd this is all can access prior to December can access emails via OWA and outlook on the LAN and WAN. The problem arises when you try and connect a user to a new machine. Indeed i am an administrator and i have installed a clean version of win 10 pro installed outlook but cannot connect to exchange . I can connect using OWA no problem at all. The problem is either a trust issue or like you say a certificate problem.
    No one who is connected to the domain with an account is having a problem as they already have the trust relationship in place.

    I think what will be useful if i send you a copy of the exchange servers application log events, you may be able to determine the exact problem.[68457-application-log-16-02-20221.txt][1]

    do you have an email i could send the application log to please

    i think a new certificate maybe required if this is the case do you have a step by step guide please . See what you think with the application logs , there maybe something you spot that is the cause.


  2. Neil Jones 21 Reputation points
    2021-02-19T22:45:10.63+00:00

    Hi JoyZang,
    Thank you very much for that and just to let you know I have followed exactly what you suggested and yes it has corrected the problem !!!! cannot thank you enough as other advice I received did not correct the problem.
    The odd thing was it said the certificate was there and ok but clearly it wasn't the case plus now the done what you said the thumbprint has changed and i can now connect Outlook from the LAN and WAN with no problems.

    Thanks a million
    Neil

    0 comments No comments

Your answer

Answers can be marked as Accepted Answers by the question author, which helps users to know the answer solved the author's problem.