If you have a network adapter, but your network is not functioning or the cable is unplugged, you will receive Systent Event log entries similar to:

        Event Type:                                      Error Event Source: W3SVC Event Category:                                       None Event ID: 105                                       Date: 1/21/2000                                       Time: 2:53:08 PM                                       User: N/A                                       Computer: Computername                                      Description: The server was unable to register the administration tool discovery information. The                                      administration tool may not be able to see this server. The data is the error code.                                      Data: 000004c6                                       Event Type: Error                                       Event Source: SMTPSVC                                       Event Category: None                                       Event ID: 105                                       Date: 1/21/2000                                       Time: 2:53:08 PM                                       User: N/A                                       Computer: Computername Description: The server was unable to register the administration tool discovery                                      information. The administration tool may not be able to see this server. The data is the error code.                                      Data: 000004c6                                       Event Type: Error                                       Event Source: NNTPSVC                                       Event Category: None                                       Event ID: 105                                       Date: 1/21/2000                                       Time: 2:53:08 PM                                       User: N/A                                       Computer: Computername                                      Description: The server was unable to register the administration tool discovery information. The                                      administration tool may not be able to see this server. The data is the error code.                                      Data: 000004c6 
Plug in your cable, or fix the network, to stop the events from logging.