Exchange Server 2013 退信，Error :0x80040305-0x0004de-0x00054a with event 9646

問題描述:
Exchange Server 2013 用戶收到退信 Error :0x80040305-0x0004de-0x00054a with event 9646，User mailbox has hit session limits

解決方法:
1. On the mailbox server, click [Start], click [run], type “regedit”, and then click [OK].
2. Expand the following registry subkey:
\\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeIS\ParametersSystem
3. Right-click [ParametersSystem], point to New, and then click Key.
4. Type “MaxObjsPerMapiSession”, and then press ENTER to name the new subkey.
5. Right-click [MaxObjsPerMapiSession], click New, and then click [DWORD] Value.
6. Type Object_type, and then press ENTER to name the object.
    In most cases, the objects “objtMessage” , “objtFolder” and “objtFolderView” would exceed the 
    limitation, so we could create three objects for all of them(Replace Object_type with    
    objtMessage, objtFolder or objtFolderView).
7. Right-click Object_type, and then click Modify.
8. In the Value data box, type the number of objects that you want to limit this entry to, and then    
   click OK. For example, type 500 to increase the value for the objtMessage object. The default    
   value is 250. The default value of “objtFolder” and “objtFolderView” are all 500.
9.Restart Information Store Services.

參考知識文件： 
A user mailbox has hit session limits
http://technet.microsoft.com/en-us/library/ff360476(v=EXCHG.140).aspx