Event ID: 4
After demoting a domain controller we are seeing an issue that the old server keeps being assigned the wrong IP by the DNS server which is the new DC

Log Name: System
Source: Microsoft-Windows-Security-Kerberos
Date: 15/06/2017 07:39:39
Event ID: 4
Task Category: None
Level: Error
Keywords: Classic
User: N/A
Computer: server.domain.suffix
Description:
The Kerberos client received a KRB_AP_ERR_MODIFIED error from the server SERVER$. The target name used was cifs/otherserver.domain.suffix. This indicates that the target server failed to decrypt the ticket provided by the client. This can occur when the target server principal name (SPN) is registered on an account other than the account the target service is using. Ensure that the target SPN is only registered on the account used by the server. This error can also happen if the target service account password is different than what is configured on the Kerberos Key Distribution Center for that target service. Ensure that the service on the server and the KDC are both configured to use the same password. If the server name is not fully qualified, and the target domain (domain.suffix) is different from the client domain (domain.suffix), check if there are identically named server accounts in these two domains, or use the fully-qualified name to identify the server.
Event Xml:



4
0
2
0
0
0x80000000000000

26673


System
server.domain.suffix



SERVER$
domain.suffix
cifs/argofieldserver.domain.suffix
domain.suffix





It happens every night...

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