1 lync/ exchange troubleshoot guide - …dbmanagement.info/microsoft/lync_exchange... · page 4 of...

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1 LYNC/ EXCHANGE TROUBLESHOOT GUIDE

TABLE OF CONTENTS

1 Lync/ Exchange Troubleshoot Guide ................................. 1

2 Troubleshooting Exchange Configuration/Functionality .... 2

2.1.1 ENABLING EXCHANGE TRACING ........................................................................... 2

2.1.2 EXCHANGE PROTOCOL LOGS ............................................................................... 3

2.1.3 VERIFYING CONNECTION BETWEEN LYNC AND EXCHANGE SERVER ............................... 4

2.1.4 TSG: CHECKING TENANT PROVISION/EXISTING IN ACS .............................................. 5

2.1.5 TSG: AUTODISCOVER AND/OR EWS REQUESTS FAIL WITH SSL/TLS ERRORS, “THE

UNDERLYING CONNECTION WAS CLOSED: COULD NOT ESTABLISH TRUST RELATIONSHIP FOR THE

SSL/TLS SECURE CHANNEL” ....................................................................................... 6

2.1.6 TSG: "UNABLE TO READ DATA FROM THE TRANSPORT CONNECTION: AN EXISTING

CONNECTION WAS FORCIBLY CLOSED BY THE REMOTE HOST." ........................................... 7

2.1.7 TSG: CREATEAPPACTASTOKEN FAILED, EX=STORECONFIGEXCEPTION:

CODE=ERROROAUTHCONFIGISSUER, REASON=CANNOT LOCATE ISSUER. ENSURE CONFIGURED

LOCAL/TENANT/GLOBAL ISSUERS ARE ACCEPTED ............................................................ 8

2.1.8 TSG: LYNCACS RST REQUEST FAILS WITH ACS50024: JWT TOKEN IS INVALID. ACS50028:

PRINCIPAL WITH NAME… .......................................................................................... 9

2.1.9 TSG: LYNC ACS RST REQUEST FAILS WITH ACS50027: JWT TOKEN IS INVALID ............ 9

2.1.10 TSG: CLIENT SIGNS IN USING WINDOWS AUTH .................................................... 11

2.1.11 TSG: AUTODISCOVER/EWS FAILS WITH OAUTHCONFIGEXCEPTION/

CRYPTOGRAPHICEXCEPTION KEYSET DOES NOT EXIST ................................................... 12

2.1.12 TSG: AUTODISCOVER/EWS REQUESTS FAIL WITH 401 REASON="THE TOKEN HAS INVALID

SIGNATURE.";ERROR_CATEGORY="INVALID_SIGNATURE" ............................................... 14

2.1.13 TSG: NOT ABLE TO REGISTER LYNC PARTNER APPLICATION AT EXCHANGE SERVER ....... 16

2.1.14 TSG: REDIRECTION STILL POINTS TO EXCHANGE ONPREM ...................................... 17

2.1.15 TSG: PICKING UP RANDOM WEB PROXY AUTOD ISSUE ........................................... 18

2.1.16 TSG: ACCESS DENIED WHEN LYNC STORAGE CMDLET EXECUTED .............................. 20

3 Lync-ACS-Exchange Message Flow ................................. 22

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2 TROUBLESHOOTING EXCHANGE CONFIGURATION/FUNCTIONALITY

2.1.1 ENABLING EXCHANGE TRACING

Run "extra" from a command shell to bring up Microsoft Exchange Troubleshooting Assistant. Click “Cancel this check” if Checking for Updates starts executing.

Click “Select a task”.

Click “Trace Control”, note the default trace folder/file path, e.g. C:\Users\Administrator\ExchangeDebugTraces.etl

Click “Set Manual Trace Tags”

Select trace tags and components relevant to the functionality being troubleshooted.

For AuthN/AuthZ issues, select Security component and all

trace tags (should include OAuth).

Click “Start Tracing”,

Repro the issue and run through the scenario you’re troubleshooting.

Click “Stop Tracing Now”, note the trace log path, e.g c:\Users\Administrator\ExchangeDebugTraces.etl

Convert .ETL files to text using one of the following methods :

For Exchange deployed via Lync VM Test infra: Use RPC

Trace Decoder tool

Exchange support tool has a RPC Trace Decoder tool includes a Get-EtwTrace command.

1. Install Exchange Support Tool from c:\Exchange15\Debugging\Exchange14SupportTools.ms

i, must use .msi built with Exchange.

2. Copy

"c:\Exchange15\Debugging\internal.exchange.shared

.Win32.dll"

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"C:\Program Files\Microsoft\Exchange

Support\Tools\"

3. In the support shell (You can launch the support shell by

opening <D:\Program Files\Microsoft\Exchange Support\Tools and double clicking

RpcTD_DebugConsole.psc1>), run

Get-EtwTrace

c:\Users\Administrator\ExchangeDebugTraces.etl |

export-csv

c:\users\Administrator\ExchangeDebugTraces.csv

For Exchange deployed via http://tdsweb: Use ExTrace.exe

Use ExTrace.exe to convert .ETL files to text, for example:

extrace

c:\Users\Administrator\ExchangeDebugTraces.etl

For more info read… How to collect Exchange Product traces

More verbose version of above steps.

How to view Exchange trace files.

Describes how to view tracing real time and convert .ETLs to CSV.

2.1.2 EXCHANGE PROTOCOL LOGS

CSV based protocol logs used for diagnostics and reporting are stored in: %ProgramFiles%\Microsoft\Exchange

Server\V15\Logging\Ews

%ProgramFiles%\Microsoft\Exchange

Server\V15\Logging\AutoDiscover

Below are some of the fields logged… DateTime,RequestId,AuthenticationType,IsAuthenticated,AuthenticatedUser,Organization,UserAgent,ClientIpAddress,ServerHostName,SoapAction,HttpStatus,RequestSize,ResponseSize,ErrorCode,ImpersonatedUser,Cookie,CorrelationGuid,BeginBudgetConnections,EndBudgetConnections,BeginBudgetH

http://tdsweb/

http://exdn/commonhowto/CommonNonCoding/Pages/HowtocollectExchangeProductTrace.aspx

http://exdn/commonhowto/CommonNonCoding/Pages/HowtoViewExchangeTraceFiles.aspx

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angingConnections,EndBudgetHangingConnections,BeginBudgetAD,EndBudgetAD,BeginBudgetCAS,EndBudgetCAS,BeginBudgetRPC,EndBudgetRPC,BeginBudgetFindCount,EndBudgetFindCount,BeginBudgetSubscriptions,EndBudgetSubscriptions,MDBResource,MDBHealth,MDBHistoricalLoad,ThrottlingPolicy,ThrottlingDelay,ThrottlingRequestType,TotalDCRequestCount,TotalDCRequestLatency,TotalMBXRequestCount,TotalMBXRequestLatency,TotalExchangePrincipalLatency,TotalAuthNLatency,TotalAuthZLatency,PreExecutionLatency,CoreExecutionLatency,TotalRequestTime,GenericInfo,AuthenticationErrors,GenericErrors

2.1.3 VERIFYING CONNECTION BETWEEN LYNC AND EXCHANGE

SERVER

1) Run Lync Server Management Shell in FE

2) Checking connection => Test-CsExStorageConnectivity –Sipurl [email protected] –Verbose

3) Checking notification => Test-CsExStorageNotification –Sipurl [email protected] –Verbose

Notification works only if Storage Web Service is running. Refer the screenshot below.

mailto:[email protected]


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2.1.4 TSG: CHECKING TENANT PROVISION/EXISTING IN ACS

If tenant does not provision correctly or configured, it may cause problem

in service scenario between Lync and Exchnage.

Copy this to your local machine and execut “AcsConfig CheckTenantExist -

Env INT-SN1-004 -Name 7e36e953-bd60-499f-9227-9c0958bb0ebb”

highlights are different based on your target/tenant. The following

screenshot is expected if tenant provisioned correctly. “acsconfig ?” gives

us more option.

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2.1.5 TSG: AUTODISCOVER AND/OR EWS REQUESTS FAIL WITH

SSL/TLS ERRORS, “THE UNDERLYING CONNECTION WAS

CLOSED: COULD NOT ESTABLISH TRUST RELATIONSHIP FOR

THE SSL/TLS SECURE CHANNEL”

Autodiscover and/or EWS requests fail with SSL/TLS errors

The request failed. The underlying connection was closed: Could not

establish trust relationship for the SSL/TLS secure channel. --->

System.Net.WebException: The underlying connection was closed: Could

not establish trust relationship for the SSL/TLS secure channel. --->

System.Security.Authentication.AuthenticationException: The remote

certificate is invalid according to the validation procedure.

at

Microsoft.Exchange.WebServices.Data.EwsHttpWebRequest.Microsoft.Exch

ange.WebServices.Data.IEwsHttpWebRequest.GetResponse()

at

Microsoft.Exchange.WebServices.Autodiscover.AutodiscoverRequest.Intern

alExecute()

--- End of inner exception stack trace ---

at

Microsoft.Exchange.WebServices.Autodiscover.AutodiscoverRequest.Intern

alExecute()

As of CL#977086 for Office15:2245853, Lyss no longer ignores cert errors

(e.g. subject mismatch), need to either:

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A) Ensure IIS hosting EWS and Autodiscover web services is configured

with server certificates exactly/wildcard matching the fqdn of requests that

LYSS sends.

B) Or, less preferably, disable checking certs in LYSS's LysSvc.exe.config

file (see LyssTestSetup.cmd in CL#977086).

Try using Fiddler (enabled SSL) to track down which requests are failing

due to DNS and/or cert issues, if you are

new to fiddler consider reading VoIP is

not a Four Letter Word.

HACK: Suppress “Mismatch Address”

ceritificate errors when running Fiddler

while LYSService and unit test client are

running,configure via tools menu

fiddler options menu item HTTPs tab to capture HTTPS, decrypt

HTTPS and ignore server cert errors:

2.1.6 TSG: "UNABLE TO READ DATA FROM THE TRANSPORT

CONNECTION: AN EXISTING CONNECTION WAS FORCIBLY

CLOSED BY THE REMOTE HOST."

- Autodiscover, OWA and other functionality dependant on backend IIS

hosted web services fails with

"Unable to read data from the transport connection: An existing connection

was forcibly closed by the remote host."

- Application event log contains warning entries logged by FrontEnd HTTP

Proxy about unhandled exceptions.

http://www.fiddler2.com/

http://msblogs/quentinb/Lists/Posts/ViewPost.aspx?ID=2

http://msblogs/quentinb/Lists/Posts/ViewPost.aspx?ID=2

http://www.fiddler2.com/

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Backend website is misconfigured.

Configure binding for backend website with appropriate certificate. Select a

wildcard cert for a single Exchange Server deployment handling requests

for multiple endpoints (e.g. Autodiscover, EWS, etc..).

2.1.7 TSG: CREATEAPPACTASTOKEN FAILED,

EX=STORECONFIGEXCEPTION:

CODE=ERROROAUTHCONFIGISSUER, REASON=CANNOT

LOCATE ISSUER. ENSURE CONFIGURED

LOCAL/TENANT/GLOBAL ISSUERS ARE ACCEPTED

CreateAppActAsToken failed, ex=StoreConfigException: code=ErrorOAuthConfigIssuer, reason=Cannot locate issuer. Ensure configured local/tenant/global issuers are accepted, host=autodiscover.exhb-99915dom.extest.microsoft.com, acceptedIssuers=microsoft.lync@ocsmgmt1.rtmp.selfhost.corp.microsoft.com,[email protected]

Neither the local or tenant configuyred issuers match the "acceptedIssuers"

listed. Could be Lync and/or Exchange misconfiguration.

Examine previous tracing statements for this activity and check/fix issuer

identifier(s) registered with Lync/Exchange.

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2.1.8 TSG: LYNCACS RST REQUEST FAILS WITH ACS50024: JWT

TOKEN IS INVALID. ACS50028: PRINCIPAL WITH NAME…

ACS50024: JWT token is invalid. ACS50028: Principal with name

\u002700000004-0000-0ff1-ce00-000000000000@b269bfba-7188-4a1f-

93a7-a42831454e77\u0027 is not a known principal.

Mismatch between -ServiceName value specified in Lync's Set-

CSOAuthConfiguration and the application identifier registered with ACS

(via STSCfg.exe -addclient)

Ensure Lync's configured application identifier (default value 00000004-

0000-0ff1-ce00-000000000000) is registered with ACS and Exchange.

2.1.9 TSG: LYNC ACS RST REQUEST FAILS WITH ACS50027:

JWT TOKEN IS INVALID

Lync to ACS RST request fails with ACS50027: JWT token is

invalid. Example failure response:

HTTP/1.1 400 Bad Request

Cache-Control: private

Content-Type: application/json; charset=utf-8

x-ms-request-id: 18a9461e-e407-42ca-865f-4172c2cf16cb

X-Content-Type-Options: nosniff

Date: Tue, 07 Aug 2012 19:04:03 GMT

Content-Length: 273

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{"error":"invalid_client","error_description":"ACS50027: JWT token is

invalid. \r\nTrace ID: 18a9461e-e407-42ca-865f-

4172c2cf16cb\r\nTimestamp: 2012-08-07

19:04:04Z","error_codes":[50027],"timestamp":"2012-08-07

19:04:04Z","trace_id":"18a9461e-e407-42ca-865f-4172c2cf16cb"}

Failure can be due to variety of configuration issues, most probable cause

is that certificate used to sign the token doesn’t match the certificate

registered with the ACS tenant.

Verify configuration is correct. ACS traces maybe required to troubleshoot

some issues, traces for ACS INT environment can be accessed by dev/test

folks. Search for ACS traces by traceID and timestamp returned in the RST

response from ACS. Traces for Dogfood/Production environments are

restricted to ACS Team/Ops.

Viewed ACS traces using failure response above: https://test1.diagnostics.monitoring.core.windows.net/content/search/search.html?table=AadIntSN1WADLogsTable&start=2012-08-07+19%3a00%3a00Z&end=2012-08-07+19%3a10%3a00Z&query=%22Message.Contains(%22%2218a9461e%22%22)%22&utc=True Reading through the ACS Traces revealed that request failed due to token signature mismatch, the token was signed with a different certificate to what’s registered with ACS “ACS50027: JWT token is invalid.Microsoft.IdentityModel.Tokens.FailedAuthenticationException : Invalid signature.”

https://test1.diagnostics.monitoring.core.windows.net/content/search/search.html?table=AadIntSN1WADLogsTable&start=2012-08-07+19%3a00%3a00Z&end=2012-08-07+19%3a10%3a00Z&query=%22Message.Contains(%22%2218a9461e%22%22)%22&utc=True





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Fixed by verifying cert registered with ACS and fixed Lync configuration: set-CsCertificate -Type OAuthTokenIssuer -Thumbprint ac14159171f9b7a763300debd09057feaf044f38

2.1.10 TSG: CLIENT SIGNS IN USING WINDOWS AUTH

Lync Client application cannot sign in

Authentication may be using Live ID

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In Lync Management Shell of Server VM:

1) Import-Module lync

2) Import-Module lynconline

3) Set-CsHostedWebAuthConfiguration -

UseClientCertAuthForWindowsAuth 0 -UseWsFedAuth 0 -Verbose

4) Set-CsWebServiceConfiguration -UseWindowsAuth 1 -

UseCertificateAuth 1 –Verbose

5) Set-CsProxyConfiguration -DisableNtlmFor2010AndLaterClients 0 –

Verbose

6) Edit hosts file : Server IP address(192.168.0.240) pool0.vdomain.com

2.1.11 TSG: AUTODISCOVER/EWS FAILS WITH

OAUTHCONFIGEXCEPTION/ CRYPTOGRAPHICEXCEPTION

KEYSET DOES NOT EXIST

OAuth fails, event log entry/tracing contains…

UnsupportedStoreException: code=ErrorIncorrectExchangeServerVersion,

reason=GetUserSettings failed, [email protected],

Autodiscover

Uri=https://autodiscover.pocket.org/autodiscover/autodiscover.svc,

Autodiscover WebProxy=<NULL> --->

Microsoft.Exchange.WebServices.Data.ServiceRequestException: The

request failed. The request was aborted: The request was canceled. --->

System.Net.WebException: The request was aborted: The request was

canceled. ---> Microsoft.Rtc.Internal.Storage.OAuthConfigException:

Certificate with <SerialNumber, 791eebc300000000004f> by

<IssuerName, CN=myca> does not have private key or it is inaccessible or

not RSA, ex=System.Security.Cryptography.CryptographicException:

Keyset does not exist


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Either private key is missing from personal certificate imported into Lync

Front End’s machine store, and/or “Network Service” has not been granted

permissions to access the private key. Enable access from certificate

manager MMC snap-in:

Grant permissions to “Network Service”, for example:

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2.1.12 TSG: AUTODISCOVER/EWS REQUESTS FAIL WITH 401

REASON="THE TOKEN HAS INVALID

SIGNATURE.";ERROR_CATEGORY="INVALID_SIGNATURE"

Lync to Exchange autodiscover fails, Exchange returns 401 with x-ms-

diagnostics: 2000000;reason="The token has invalid

signature.";error_category="invalid_signature"

TL_VERBOSE(TF_DIAG) [1]35B4.1E14::05/11/2012-

22:55:37.451.0198ad72

(Lyss,ExchangeContext.EwsTraceListener.Trace:exchangecontext.cs(631))[

3676575611]type=AutodiscoverResponseHttpHeaders, msg=<Trace

Tag="AutodiscoverResponseHttpHeaders" Tid="29" Time="2012-05-11

22:55:37Z">

HTTP/1.1 401 Unauthorized

request-id: 3f2ca142-ab5b-48c3-bd04-14d60d3fccb9

X-FEServer: L04-OCG

x-ms-diagnostics: 2000000;reason="The token has invalid

signature.";error_category="invalid_signature"

Server: Microsoft-IIS/7.5

WWW-Authenticate: Bearer client_id="00000002-0000-0ff1-ce00-

000000000000", trusted_issuers="00000004-0000-0ff1-ce00-

[email protected],00000002-0000-0ff1-ce00-

[email protected]", error="invalid_token",Basic

realm="autodiscover.pocket.org",Negotiate,NTLM

X-Powered-By: ASP.NET

Date: Fri, 11 May 2012 22:55:35 GMT

Content-Length: 0

</Trace>

mailto:[email protected],[email protected]



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TL_ERROR(TF_STACKTRACE) [1]35B4.1E14::05/11/2012-

22:55:37.452.0198ad73

(Lyss,ExchangeContext.GetUserEwsSettings:exchangecontext.cs(568))[367

6575611]UnsupportedStoreException:

code=ErrorIncorrectExchangeServerVersion, reason=GetUserSettings

failed, [email protected], Autodiscover

Uri=https://autodiscover.pocket.org/autodiscover/autodiscover.svc,

Autodiscover WebProxy=<NULL> --->

Microsoft.Exchange.WebServices.Data.ServiceRequestException: The request

failed. The remote server returned an error: (401) Unauthorized. --->

System.Net.WebException: The remote server returned an error: (401)

Unauthorized.

Exchange does not like the token signature, this indicates a mismatch

between the cert Lync signed the token with and the cert that Exchange is

configured with for the Lync Partner application.

Verify/correct cert that Lync is configured with and cert registered with

Exchange. Verify cert Exchange is configured with using Exchange

management shell’s Get-PartnerApplication, copy-paste the base64

encoded certificate data into a .cer text file, save and open the .cer file

from explorer to see the cert details.

Lync Storage Service picks up configuration changes within

seconds. Exchange requires iisreset in order for EWS to pickup recent

configuration changes. In addition, Exchange only periodically refreshes

cert data by query the AuthMetadataUrl configure for Lync partner

application. Force Exchange to query Lync’s autodiscover endpoint for

latest certs by setting AuthMetadataUrl to the existing value, e.g. Set-

PartnerApplication "Lync" -AuthMetadataUrl

https://pool1.pocket.org/metadata/json/1


https://pool1.pocket.org/metadata/json/1

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2.1.13 TSG: NOT ABLE TO REGISTER LYNC PARTNER

APPLICATION AT EXCHANGE SERVER

Sometimes, Exchange Management Shell cmdelt, New-PartnerApplication

returns 502 bad gateway in spite of AuthMetaUrl can be reachable. This is

Exchange bug and tracking #3076377.

[PS] D:\Program Files\Microsoft\Exchange Server\V15\Scripts>New-

PartnerApplication [email protected] -Enabled $true -AuthMetadataUrl

https://O04-mcs.exchangedc4.com/metadata/json/1 -LinkedAccount

"exchangedc4.com/Users/Exchange Online-ApplicationAccount"

Cannot acquire auth metadata document from 'https://O04-

mcs.exchangedc4.com'/metadata/json/1'. Error: The underlying connection

was closed: Could not establish trust relationship for the SSL/TLS secure

channel..

+ CategoryInfo : ResourceUnavailable: (:) [New-

PartnerApplication], AuthMetadataClientException

+ FullyQualifiedErrorId :

150AC300,Microsoft.Exchange.Management.SystemConfigurationTasks.Ne

wPartnerApplication

+ PSComputerName : o04-mcs.exchangedc4.com

Cannot acquire auth metadata document from 'https://O04-

mcs.exchangedc4.com'. Error: The remote server returned an

error: (502) Bad Gateway..

+ CategoryInfo : ResourceUnavailable: (:) [New-

PartnerApplication], AuthMetadataClientException

+ FullyQualifiedErrorId :

AFABAD18,Microsoft.Exchange.Management.SystemConfigurationTasks.Ne

wPartnerApplication

+ PSComputerName : o04-mcs.exchangedc4.com


https://o04-mcs.exchangedc4.com/metadata/json/1

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1) Use IPAddress instead of O04-mcs.exchangedc4.com

2) Download metadata manually and copy to Exchange IIS

2.1.14 TSG: REDIRECTION STILL POINTS TO EXCHANGE ONPREM

The redirection scenario, such as mailbox user migrated from Exchange

onprem to online, the redirected autodiscover url points still 1st Exchange

onprem as screenshot shown below.

This blocks to access Exchange online box and redirection scenario will not

work.

Check the following [PS] C:\Program Files\Microsoft\Exchange Server\V15\Scripts>New-AcceptedDomain lysshybrid.msol-test.com -DomainName lysshybrid.msol-test.com

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2.1.15 TSG: PICKING UP RANDOM WEB PROXY AUTOD ISSUE

This failed lyss connectivity to Exchange.

Add the following to %programfiles%\Microsoft Lync Server

2013\Server\Core\LysSvc.exe.config

<system.net>

<settings>

<servicePointManager

checkCertificateName="true" />

</settings>

<defaultProxy>

<proxy

usesystemdefault="true"

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proxyaddress="http://itgproxy.redmond.corp.microsoft.com:80"

bypassonlocal="True"

/>

<bypasslist>

<add address="[a-z]+\.lcspeer\.lcesa\.pri\.local" />

<add address="[a-z]+\.lcesa\.pri\.local" />

<add address="firstsite\.exchangelabs\.live-int\.com" />

</bypasslist>

</defaultProxy>

</system.net>

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2.1.16 TSG: ACCESS DENIED WHEN LYNC STORAGE CMDLET

EXECUTED

The current account does not belong to RTC Group.

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Add the account logged in currently to RTC Group (Computer

Management=>Local Users and Groups => Groups) below and then log

out/back in.

RTC Component Local Group

RTC Server Local Group

RTC Local User Administrators

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3 LYNC-ACS-EXCHANGE MESSAGE FLOW

|Agent LYSS| |ACS| | Exchange | |AutoD | EWS| ------> - Lync agent/LYSS-client sends request to LYSS WCF based Storage Service. LYSS internally dispatches request to an Adaptor which may need to perform some EWS operation. -----------------> - LYSS sends get user setting request to Exchange Autodiscover WS. <----------------- - Exchange fails to find OAuth token in request header returns 401. -------> - LYSS sends RST request to ACS for app token signed with cert trusted by Exchange, requests access for AutoD fqdn resource. - This step is skipped if token is already cached. <------- - ACS returns app token for AutoD resource. -----------------> - LYSS resends get user setting request with AppActAs token containing app token signed by ACS. <----------------- - Exchange Autodiscover WS verifies OAuth token and internally does AD/store lookups for User settings such as EWS endpoint. ---------------------------> - LYSS sends EWS request (e.g. CreateItem) to EWS endpoint, <--------------------------- - Exchange fails to find OAuth token in request header returns 401. -------> - LYSS sends RST request to ACS for app token signed with cert trusted by Exchange, requests access for EWS fqdn resource. - This step is skipped if token is already cached. <------- - ACS returns app token for EWS resource. ---------------------------> - LYSS resends EWS request (e.g. CreateItem) to EWS endpoint with AppActAs token containing app token signed by ACS. <--------------------------- - Exchange performs EWS operation and internally interacts with various resources depending on the operation. Eventually returning a response.

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