Just another IT Guy from China https://docs.microsoft.com/archive/blogs/tahuan/feed.xml Wed, 17 Apr 2019 03:36:01 GMT en-US hourly 1 One good example of making the best of your Azure Subscriptions https://docs.microsoft.com/archive/blogs/tahuan/one-good-way-to-make-the-best-of-your-azure-subscriptions Fri, 21 Apr 2017 03:06:38 GMT https://blogs.technet.microsoft.com/tahuan/?p=95 this post , and you will see how easy it is to implement one in Azure. For those who are blocked from accessing Google/Youtube, Facebook and etc, it is your friend, really!  ]]> Exchange Server 2013 Performance https://docs.microsoft.com/archive/blogs/tahuan/exchange-server-2013-performance Sun, 03 May 2015 18:32:20 GMT https://blogs.technet.microsoft.com/tahuan/2015/05/03/exchange-server-2013-performance/ https://aka.ms/exchangeperf

]]> EMSMDB32 https://docs.microsoft.com/archive/blogs/tahuan/emsmdb32 Sun, 04 Jan 2015 23:42:34 GMT https://blogs.technet.microsoft.com/tahuan/2015/01/04/emsmdb32/ EMSMDB32 is a dll file you may have seen a lot if you have ever diagnosed Outlook connectivity issues.

EMSMDB is short for Electronic Messaging System Microsoft Database Provider. As its name implies, it's a database provider. As such, it enables reading and writing messages to an Exchange store.

Since Outlook 2007, EMSMDB is also an address book provider as well as a transport provider. In other words, Outlook calls the methods provided by EMSMDB32 to access an Exchange store, to open the address book, and to submit messages to Exchange server.

Internally, the role of EMSMDB32 is to receive the calls from upper MAPI layers and convert them into ROP calls that are understood by Exchange.

The common methods provided by EMSMDB32 are EcDoConnect, EcDoDisConnect, EcDoRpcExt2, EcRRegisterPushNotification. At transport layer (RPC), each of these methods has a corresponding Operation number (OPNUM). For the details on this relationship, see MSDN article https://msdn.microsoft.com/en-us/library/ee178982(v=exchg.80).aspx

That's some basic stuff about EMSMDB. Until next time.

]]> Outlook's Architecture https://docs.microsoft.com/archive/blogs/tahuan/outlooks-architecture Sun, 04 Jan 2015 23:21:17 GMT https://blogs.technet.microsoft.com/tahuan/2015/01/04/outlooks-architecture/ When you are troubleshooting Outlook connectivity issues, you may heard a lot of items, such as MAPI, RPC, etc. If you ever wonder what they are and how they fit together to make Outlook connectivity possible, you need to have a understanding of Outlook's architecture.

In General, there are several layers when it comes to Outlook connecting to a messaging system (like Exchange):

  • Outlook
  • MAPI Layer
  • Service Provider Layer
  • Transport Provider
  • IP/Ethernet Layer

The interfaces between layers are COM interfaces. Each layer exposes one or more COM interfaces as well as methods on these interfaces.

For Outlook connectivity to work, each layer needs to function as expected. I made a figure  and hope that it helps with understanding of these layers.

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