The log file contains the following error with the Principal user reference matching your SystemUserId:
09:17:01| Error| Exception : Principal user (Id=4294cbf9-7534-e311-8b6d-6c3be5a8f660, type=8) is missing prvReadMailbox privilege (Id=8e17de3a-5a69-479c-9535-1f7be75b2987) at Microsoft.Crm.Application.Platform.ServiceCommands.PlatformCommand.XrmExecuteInternal()
at Microsoft.Crm.Application.Platform.ServiceCommands.RetrieveCommand.Execute()
at Microsoft.Crm.Caching.MailboxWebServiceCacheLoader.LoadCacheData(Guid key, IOrganizationContext context)
at Microsoft.Crm.Caching.ClientCacheLoaderProxy`2.LoadCacheData(TKey key, IOrganizationContext context)
at Microsoft.Crm.Caching.CrmMultiOrgCacheBase`2.CreateEntry(TKey key, IOrganizationContext context)
at Microsoft.Crm.Caching.CrmMultiOrgCacheBase`2.LookupEntry(TKey key, IOrganizationContext context)
at Microsoft.Crm.Application.Outlook.Config.OutlookConfigurator.InitializeMapiStoreForFirstTime()
at Microsoft.Crm.Application.Outlook.Config.OutlookConfigurator.Configure(IProgressEventHandler progressEventHandler)
at Microsoft.Crm.Application.Outlook.Config.ConfigEngine.Configure(Object stateInfo)
If the user is a member of a team that only has user level Read access to the Mailbox entity and they do not have a security role assigned directly to their user record with user level Read access to the Mailbox entity, the log file contains the following error with the Owner Id and Calling User reference matching your SystemUserId:
17:16:47| Error| Exception : SecLib::AccessCheckEx failed. Returned hr = -2147187962, ObjectID: 7f27247a-dda1-e411-80d9-fc15b4285da4, OwnerId: 4294cbf9-7534-e311-8b6d-6c3be5a8f660, OwnerIdType: 8 and CallingUser: 4294cbf9-7534-e311-8b6d-6c3be5a8f660. ObjectTypeCode: 9606, objectBusinessUnitId: 8bce1ea5-1e75-e411-80cf-c4346bac89f4, AccessRights: ReadAccess
Server stack trace:
at System.ServiceModel.Channels.ServiceChannel.HandleReply(ProxyOperationRuntime operation, ProxyRpc& rpc)
at System.ServiceModel.Channels.ServiceChannel.Call(String action, Boolean oneway, ProxyOperationRuntime operation, Object[] ins, Object[] outs, TimeSpan timeout)
at System.ServiceModel.Channels.ServiceChannelProxy.InvokeService(IMethodCallMessage methodCall, ProxyOperationRuntime operation)
at System.ServiceModel.Channels.ServiceChannelProxy.Invoke(IMessage message)
Exception rethrown at [0]:
at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)
at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)
at Microsoft.Xrm.Sdk.IOrganizationService.Retrieve(String entityName, Guid id, ColumnSet columnSet)
at Microsoft.Xrm.Sdk.WebServiceClient.OrganizationWebProxyClient.<>c__DisplayClass4.<RetrieveCore>b__3()
at Microsoft.Xrm.Sdk.WebServiceClient.WebProxyClient`1.ExecuteAction[TResult](Func`1 action)
at Microsoft.Xrm.Sdk.WebServiceClient.OrganizationWebProxyClient.RetrieveCore(String entityName, Guid id, ColumnSet columnSet)
at Microsoft.Xrm.Sdk.WebServiceClient.OrganizationWebProxyClient.Retrieve(String entityName, Guid id, ColumnSet columnSet)
at Microsoft.Crm.Application.SMWrappers.ClientOrganizationServiceProxyBase.Retrieve(String entityName, Guid id, ColumnSet columnSet)
at Microsoft.Crm.Application.Outlook.Config.ServerInfo.LoadMailboxInfo(IClientAuthProvider`1 orgAuthProvider)
at Microsoft.Crm.Application.Outlook.Config.ServerInfo.LoadUserInfo(IClientAuthProvider`1 orgAuthProvider)
at Microsoft.Crm.Application.Outlook.Config.ServerInfo.Initialize(Uri discoveryUri, OrganizationDetail selectedOrg, String displayName, Boolean isPrimary, IClientAuthProvider`1 authenticatedProvider)
at Microsoft.Crm.Application.Outlook.Config.ServerForm.LoadDataToServerInfo()
at Microsoft.Crm.Application.Outlook.Config.ServerForm.<InitializeBackgroundWorkers>b__3(Object sender, DoWorkEventArgs e)
at System.ComponentModel.BackgroundWorker.OnDoWork(DoWorkEventArgs e)
at System.ComponentModel.BackgroundWorker.WorkerThreadStart(Object argument)