Exchange 2013 Error - MapiExceptionUnknownUser: Unable to open message store

I am trying to install Exchange Server 2013 for days. On every try I am getting the error "MapiExceptionUnknownUser: Unable to open message store." while connecting to either ECP or OWA.

In my searches, some people says it is about Reginal Settings. I made a clean install for both Windows Server 2012 and Exchange Server 2013. I have set all reginal settings to English and US. I have installed a server for Active Directory and a seperate server for Exchange. I made everything decent and there was no error at prerequisites. There was no error after installation. But every time I try to reach ECP or OWA I get error about user.

Somebody told me creating a user on AD without mailbox would fix the problem but no.

I could open ECP page by https://< IP >/ecp/?ExchClientVer=15 with ?ExchClientVer=15 This URL doesn't work for OWA.

Could you suggest anything?

Detailed error:

Server Error in '/owa' Application.

MapiExceptionUnknownUser: Unable to open message store. (hr=0x80004005, ec=1003)
Diagnostic context:
   Lid: 55847   EMSMDBPOOL.EcPoolSessionDoRpc called [length=688]
   Lid: 43559   EMSMDBPOOL.EcPoolSessionDoRpc returned [ec=0x0][length=240][latency=15]
   Lid: 52176   ClientVersion: 15.0.516.30
   Lid: 50032   ServerVersion: 15.0.516.6030
   Lid: 23226   --- ROP Parse Start ---
   Lid: 27962   ROP: ropLogon [254]
   Lid: 17082   ROP Error: 0x3EB     
   Lid: 26937  
   Lid: 21921   StoreEc: 0x3EB     
   Lid: 27962   ROP: ropExtendedError [250]
   Lid: 1494    ---- Remote Context Beg ----
   Lid: 61208   StoreEc: 0x8004010F
   Lid: 57721   StoreEc: 0x8004010F
   Lid: 47536  
   Lid: 64952   StoreEc: 0x3EB     
   Lid: 56872   dwParam: 0xFE
   Lid: 42712   StoreEc: 0x3EB     
   Lid: 10786   dwParam: 0x0        Msg: 15.00.0516.025:ex1
   Lid: 1750    ---- Remote Context End ----
   Lid: 26849  
   Lid: 21817   ROP Failure: 0x3EB     
   Lid: 26297  
   Lid: 16585   StoreEc: 0x3EB     
   Lid: 32441  
   Lid: 1706    StoreEc: 0x3EB     
   Lid: 24761  
   Lid: 20665   StoreEc: 0x3EB     
   Lid: 25785  
   Lid: 29881   StoreEc: 0x3EB     

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. 

Exception Details: Microsoft.Mapi.MapiExceptionUnknownUser: MapiExceptionUnknownUser: Unable to open message store. (hr=0x80004005, ec=1003)
Diagnostic context:
   Lid: 55847   EMSMDBPOOL.EcPoolSessionDoRpc called [length=688]
   Lid: 43559   EMSMDBPOOL.EcPoolSessionDoRpc returned [ec=0x0][length=240][latency=15]
   Lid: 52176   ClientVersion: 15.0.516.30
   Lid: 50032   ServerVersion: 15.0.516.6030
   Lid: 23226   --- ROP Parse Start ---
   Lid: 27962   ROP: ropLogon [254]
   Lid: 17082   ROP Error: 0x3EB     
   Lid: 26937  
   Lid: 21921   StoreEc: 0x3EB     
   Lid: 27962   ROP: ropExtendedError [250]
   Lid: 1494    ---- Remote Context Beg ----
   Lid: 61208   StoreEc: 0x8004010F
   Lid: 57721   StoreEc: 0x8004010F
   Lid: 47536  
   Lid: 64952   StoreEc: 0x3EB     
   Lid: 56872   dwParam: 0xFE
   Lid: 42712   StoreEc: 0x3EB     
   Lid: 10786   dwParam: 0x0        Msg: 15.00.0516.025:ex1
   Lid: 1750    ---- Remote Context End ----
   Lid: 26849  
   Lid: 21817   ROP Failure: 0x3EB     
   Lid: 26297  
   Lid: 16585   StoreEc: 0x3EB     
   Lid: 32441  
   Lid: 1706    StoreEc: 0x3EB     
   Lid: 24761  
   Lid: 20665   StoreEc: 0x3EB     
   Lid: 25785  
   Lid: 29881   StoreEc: 0x3EB     

Source Error: 

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace: 


[MapiExceptionUnknownUser: MapiExceptionUnknownUser: Unable to open message store. (hr=0x80004005, ec=1003)
Diagnostic context:
    Lid: 55847   EMSMDBPOOL.EcPoolSessionDoRpc called [length=688]
    Lid: 43559   EMSMDBPOOL.EcPoolSessionDoRpc returned [ec=0x0][length=240][latency=15]
    Lid: 52176   ClientVersion: 15.0.516.30
    Lid: 50032   ServerVersion: 15.0.516.6030
    Lid: 23226   --- ROP Parse Start ---
    Lid: 27962   ROP: ropLogon [254]
    Lid: 17082   ROP Error: 0x3EB     
    Lid: 26937  
    Lid: 21921   StoreEc: 0x3EB     
    Lid: 27962   ROP: ropExtendedError [250]
    Lid: 1494    ---- Remote Context Beg ----
    Lid: 61208   StoreEc: 0x8004010F
    Lid: 57721   StoreEc: 0x8004010F
    Lid: 47536  
    Lid: 64952   StoreEc: 0x3EB     
    Lid: 56872   dwParam: 0xFE
    Lid: 42712   StoreEc: 0x3EB     
    Lid: 10786   dwParam: 0x0        Msg: 15.00.0516.025:ex1
    Lid: 1750    ---- Remote Context End ----
    Lid: 26849  
    Lid: 21817   ROP Failure: 0x3EB     
    Lid: 26297  
    Lid: 16585   StoreEc: 0x3EB     
    Lid: 32441  
    Lid: 1706    StoreEc: 0x3EB     
    Lid: 24761  
    Lid: 20665   StoreEc: 0x3EB     
    Lid: 25785  
    Lid: 29881   StoreEc: 0x3EB     ]
   Microsoft.Mapi.MapiExceptionHelper.InternalThrowIfErrorOrWarning(String message, Int32 hresult, Boolean allowWarnings, Int32 ec, DiagnosticContext diagCtx, Exception innerException) +61
   Microsoft.Mapi.MapiExceptionHelper.ThrowIfError(String message, Int32 hresult, IExInterface iUnknown, Exception innerException) +91
   Microsoft.Mapi.ExRpcConnection.OpenMsgStore(OpenStoreFlag storeFlags, String mailboxDn, Guid mailboxGuid, Guid mdbGuid, String& correctServerDn, ClientIdentityInfo clientIdentityAs, String userDnAs, String applicationId, Byte[] tenantHint, CultureInfo cultureInfo) +1683
   Microsoft.Mapi.MapiStore.OpenMapiStore(String serverDn, String userDn, String mailboxDn, Guid guidMailbox, Guid guidMdb, String userName, String domainName, String password, String httpProxyServerName, ConnectFlag connectFlags, OpenStoreFlag storeFlags, CultureInfo cultureInfo, Boolean wantRedirect, String& correctServerDN, ClientIdentityInfo clientIdentity, String applicationId, Client xropClient, Boolean wantWebServices, Byte[] clientSessionInfo, TimeSpan connectionTimeout, Byte[] tenantHint) +2105
   Microsoft.Exchange.Data.Storage.MailboxSession.ForceOpen(MapiStore linkedStore) +23073

[MailboxUnavailableException: Cannot open mailbox /o=GarantiServer/ou=Exchange Administrative Group (FYDIBOHF23SPDLT)/cn=Recipients/cn=14c84347a664422684ca9adedfa188c3-exad.]
   Microsoft.Exchange.Data.Storage.MailboxSession.ForceOpen(MapiStore linkedStore) +51774
   Microsoft.Exchange.Data.Storage.MailboxSession.Initialize(MapiStore linkedStore, LogonType logonType, ExchangePrincipal owner, DelegateLogonUser delegateUser, Object identity, OpenMailboxSessionFlags flags, GenericIdentity auxiliaryIdentity) +4354
   Microsoft.Exchange.Data.Storage.<>c__DisplayClass16.<CreateMailboxSession>b__14(MailboxSession mailboxSession) +156
   Microsoft.Exchange.Data.Storage.MailboxSession.InternalCreateMailboxSession(LogonType logonType, ExchangePrincipal owner, DelegateLogonUser delegatedUser, CultureInfo cultureInfo, String clientInfoString, IBudget budget, Action`1 initializeMailboxSession, InitializeMailboxSessionFailure initializeMailboxSessionFailure) +2333
   Microsoft.Exchange.Data.Storage.MailboxSession.CreateMailboxSession(LogonType logonType, ExchangePrincipal owner, DelegateLogonUser delegateUser, Object identity, OpenMailboxSessionFlags flags, CultureInfo cultureInfo, String clientInfoString, PropertyDefinition[] mailboxProperties, IList`1 foldersToInit, GenericIdentity auxiliaryIdentity, IBudget budget) +1022
   Microsoft.Exchange.Data.Storage.MailboxSession.ConfigurableOpen(ExchangePrincipal mailbox, MailboxAccessInfo accessInfo, CultureInfo cultureInfo, String clientInfoString, LogonType logonType, PropertyDefinition[] mailboxProperties, InitializationFlags initFlags, IList`1 foldersToInit, IBudget budget) +1198
   Microsoft.Exchange.Data.Storage.MailboxSession.Open(ExchangePrincipal mailboxOwner, ClientSecurityContext clientSecurityContext, CultureInfo cultureInfo, String clientInfoString) +188
   Microsoft.Exchange.Clients.Owa2.Server.Core.OwaClientSecurityContextIdentity.CreateMailboxSession(ExchangePrincipal exchangePrincipal, CultureInfo cultureInfo) +533
   Microsoft.Exchange.Clients.Owa2.Server.Core.RequestDispatcher.HandleLanguagePost(RequestContext requestContext, CultureInfo culture, String timeZoneKeyName, Boolean isOptimized, String destination) +647
   Microsoft.Exchange.Clients.Owa2.Server.Core.RequestDispatcher.DispatchIfLanguagePost(RequestContext requestContext) +642
   Microsoft.Exchange.Clients.Owa2.Server.Core.RequestDispatcher.InternalDispatchRequest(RequestContext requestContext) +620
   Microsoft.Exchange.Clients.Owa2.Server.Core.RequestDispatcher.DispatchRequest(RequestContext requestContext) +297
   Microsoft.Exchange.Clients.Owa2.Server.Core.OwaRequestHandler.OnPostAuthorizeRequest(Object sender, EventArgs e) +352
   System.Web.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +80
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +165

Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.18033

This issue was a known issue and It has been fixed by Exchange Server 2013Cumulative Update 1.

I am sure this must help you. You can make fresh install with this cumulative update file or you can install over existing Exchange 2013

Download Link