Fault: 0x800ccc1a error when outlook sends and receives mail

1、 The fault phenomenon ：

1） One of the customers  Exchange Server 2013 CAS There's a blackmail virus on the server , The customer is forced to leave the domain and shut down completely （ Not unloaded Exchange Software ）.

2） The customer reinstalls and sets up a new one CAS The server .

3） When testing the client email application , Find out Outlook POP3 The client can only send mail , Unable to receive mail ：

   

    

2、 Fault handling ：

1） stay Active Directory Computers and Users in , Delete old CAS  The computer account of the server , And clear the corresponding ADSI Information .

2） stay Exchange ECP in , Confirm no old CAS Server related information , And there are new CAS Server related information .

3） Test client , The fault is still .

4） see PopProxy state ：（ The original status is Inactive）

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