一些注意点：
具体需要做些什么，个人需要，我也不仔细说了，察看msdn就明白了。
我在开发过程中的一些注意，列一下：
1. 在单独类oAddin中处理，指定progID
指定progID
<GuidAttribute("CA940FE1-1193-411b-82DF-570A04491150"),
ProgIdAttribute("AddinForBible.olAddin")>
Public Class OutAddIn
End Class
2. 清除outlook的对象：
清除outlook的对象：
Public Sub DisposeObject(ByVal obj As Object)
'Wraps ReleaseCOMObject to provide a 'safe' disposal helper method.
Dim count As Integer
Try
If obj Is Nothing Then
Exit Try
End If
If Not Marshal.IsComObject(obj) Then
Exit Try
End If
count = Marshal.ReleaseComObject(obj)
While count > 0
count = Marshal.ReleaseComObject(obj)
End While
Catch ex As SystemException
Finally
obj = Nothing
End Try
End Sub
3. CDO1.21对象在Office的安装包里可以安装，使用例子：
设置folder的default post message 属性为 自定义 form
这个属性找了很久，msdn里没有提及，留在这里吧，以后也不太会再作outlook开发了
g_olNamespace = m_olOutlookApp.Session
g_olNamespace.Logon(, , False, False)
g_objMAPISession = New MAPI.Session
g_objMAPISession.Logon(, , False, False)
Public Function SetFolderDftMsgPostClass(ByVal sFolderID As String, ByVal sStoreID As String) As Boolean
Dim objMAPIFolder As MAPI.Folder
Dim objMAPIFields As MAPI.Fields
Const PR_DEF_POST_DISPLAYNAME = &H36E6001E '定制form的显示名字
Const PR_DEF_POST_MSGCLASS = &H36E5001E '定制form的MessageClass名称
Try
objMAPIFolder = g_objMAPISession.GetFolder(sFolderID, sStoreID)
objMAPIFields = objMAPIFolder.Fields
Try
If objMAPIFields.Item(PR_DEF_POST_MSGCLASS).value = cVerseMessageClass Then
Exit Try
End If
Catch ex As Exception
With objMAPIFields
.Add(PR_DEF_POST_DISPLAYNAME, cVerseFormName)
.Add(PR_DEF_POST_MSGCLASS, cVerseMessageClass)
End With
objMAPIFolder.Update()
End Try
Catch ex As Exception
Finally
End Try
DisposeObject(objMAPIFields)
DisposeObject(objMAPIFolder)
End Function
4. 初始化outlook对象，取得基本的对象。
初始化outlook对象，取得基本的对象。
Imports myOutlook = Microsoft.Office.Interop.Outlook
Public g_olNamespace As myOutlook.NameSpace '当前outlook session对象
Public g_oBaseFolder As myOutlook.MAPIFolder '当前outlook folder对象
Public g_olApp As myOutlook.Application '当前outlook对象
Public g_sStoreID As String
Private WithEvents m_olExplorer As myOutlook.ExplorerClass
'当前outlook explorer对象
g_olNamespace = m_olOutlookApp.Session
g_olNamespace.Logon(, , False, False)
m_olExplorer = CType(m_olOutlookApp.ActiveExplorer, myOutlook.ExplorerClass)
g_oBaseFolder = g_olNamespace.Folders.Item(foldername)
g_sStoreID = g_oBaseFolder.StoreID
取得folder对象：
namespace.folders.Item(“foldername”)
取得第一个名为foldername的folder
namespace.GetFolderFromID(sFolderID,sStoreID)
取得指定ID的folder
FolderID , StoreID
Folder.EntryID
