Event ID: 8026
Event Type: Error
Event Source: MSExchangeAL
Event Category: LDAP Operations
Description: LDAP Bind was unsuccessful on directory <Fully Qualified Domain Name of Windows domain controller>for distinguished name ''. Directory returned error:[0x51] Server Down.
Event ID: 8260
Event Type: Error
Event Source: MSExchangeAL
Event Category: Service Controller
Description: Could not open LDAP session to directory '<Fully Qualified Domain Name of Windows domain controller>' using local service credentials. Cannot access Address List configuration information. Make sure the server '<Fully Qualified Domain Name of Windows domain controller>' is running.
Event Type: Error
Event Source: MSExchangeAL
Event Category: LDAP Operations
Description: LDAP Bind was unsuccessful on directory <Fully Qualified Domain Name of Windows domain controller>for distinguished name ''. Directory returned error:[0x51] Server Down.
Event ID: 8260
Event Type: Error
Event Source: MSExchangeAL
Event Category: Service Controller
Description: Could not open LDAP session to directory '<Fully Qualified Domain Name of Windows domain controller>' using local service credentials. Cannot access Address List configuration information. Make sure the server '<Fully Qualified Domain Name of Windows domain controller>' is running.