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Hi ,
We have 3 exchange servers and we have recently disabled TLS 1.0.
Since then the users in the same servers are able to lookup for free/busy but the users mounted on other exchange servers, free/busy does not work.
We also get the event 4002 on both the servers when free/busy issues persists
Process 23020: ProxyWebRequest CrossSite from S-1-X-21-XXX8696XXXX-XXXXXXXXX-XXXXXXXXX-XXXX to https://server1.domain.com:444/EWS/Exchange.asmx failed. Caller SIDs: NetworkCredentials. The exception returned is Microsoft.Exchange.InfoWorker.Common.Availability.ProxyWebRequestProcessingException: Proxy web request failed. ---> System.Net.WebException: The underlying connection was closed: An unexpected error occurred on a send. ---> System.IO.IOException: Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host. ---> System.Net.Sockets.SocketException: An existing connection was forcibly closed by the remote host
at System.Net.Sockets.Socket.EndReceive(IAsyncResult asyncResult)
at System.Net.Sockets.NetworkStream.EndRead(IAsyncResult asyncResult)
--- End of inner exception stack trace ---
at System.Net.TlsStream.EndWrite(IAsyncResult asyncResult)
at System.Net.ConnectStream.WriteHeadersCallback(IAsyncResult ar)
--- End of inner exception stack trace ---
at System.Web.Services.Protocols.WebClientAsyncResult.WaitForResponse()
at System.Web.Services.Protocols.WebClientProtocol.EndSend(IAsyncResult asyncResult, Object& internalAsyncState, Stream& responseStream)
at System.Web.Services.Protocols.SoapHttpClientProtocol.EndInvoke(IAsyncResult asyncResult)
at Microsoft.Exchange.InfoWorker.Common.Availability.Proxy.Service.EndGetMailTips(IAsyncResult asyncResult)
at Microsoft.Exchange.InfoWorker.Common.MailTips.MailTipsApplication.EndProxyWebRequest(ProxyWebRequest proxyWebRequest, QueryList queryList, IService service, IAsyncResult asyncResult)
at Microsoft.Exchange.InfoWorker.Common.Availability.ProxyWebRequest.EndInvoke(IAsyncResult asyncResult)
at Microsoft.Exchange.InfoWorker.Common.Availability.AsyncWebRequest.EndInvokeWithErrorHandling()
--- End of inner exception stack trace ---
. Name of the server where exception originated: Server1. LID: 43532. Make sure that the Active Directory site/forest that contain the user's mailbox has at least one local Exchange 2010 server running the Availability service. Turn up logging for the Availability service and test basic network connectivity.
Kindly advice to resolve the issue.
Cheers
Priya
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@Priya Jayaraman
Hi,Priya.
From your post,I suppose that the three servers are all Exchange 2016 and added to a DAG.
What CU are you running on the servers?
To my knowledge,your problem may possibly occurs from the HTTPs proxy between Exchange servers is still using TLS1.0.
Disabling it may cause the proxy to fail which affects EWS(responsible for free/busy information)
You may need to upgrade to CU9 or later If you want to disable TLS1.0.
For more information,here are some helpful articles from Exchange Team Blog:
Exchange Server TLS guidance, part 1: Getting Ready for TLS 1.2
Exchange Server TLS guidance Part 2: Enabling TLS 1.2 and Identifying Clients Not Using It
Exchange Server TLS guidance Part 3: Turning Off TLS 1.0/1.1
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Hi Kael,
Our servers are running Exchange 2016 CU 16 & .NETFramework 4.8. Kindly advice on how to mitigate the issue.
Cheers
Priya
Hi,Priya.
Thanks for your information.
Did you follow all the steps listed in the articles above when you disable TLS1.0?
It is recommended to go through it and check if there is something left.
In addition,please also check if there are some relevant error events on the servers,for example event 4002.
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@Priya Jayaraman
Hi,
I am writing here to confirm with you how thing going now?
If you need further help, please provide more detailed information, so that we can give more appropriate suggestions.
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how do you disable the TLS? Event ID 4002 occurs, it maybe disabled by mistake i met the same issue, the free/busy doesn't work, how can i fix it?