DCOM was unable to communicate with the computer ADMIN using any of the configured protocols.

Recently I was mixed up with the following system event log.This event log was logged every 10 or 15 minutes.
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Event Type: Error
Event Source: DCOM
Event Category: None
Event ID: 10009
Date: 10/17/2007
Time: 17:05:40
User: computer\akira
Computer: computer
Description:
DCOM was unable to communicate with the computer ADMIN using any of the configured protocols.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
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There's no ADMIN computer right here. I check the microsoft website described but it didn't help me.Finally I figured out that the incorrect printer port caused the error.
I have 3 wired printer ports below.

Auto Microsoft Office Document Image Writer on ADMIN
Auto HP DeskJet 600 on ADMIN
Auto Adobe PDF on LENOVO-ADIHELXON

The ports used by those printers are
\\ADMIN\Auto Microsoft Office Document Image Writer
\\ADMIN\Auto HP DeskJet 600
\\LENOVO-ADIHELXON\Auto Adobe PDF

I created new local printer ports and assigned them for 3 printers one by one.After that I deleted 3 wired printer ports.To delete printer ports,
To delete printer ports, Open
Start Menu -> Settings -> Printers and Faxes
and Files menu -> Server Properties
You will see the 'ports' tab and can delete/add printer ports.

Finally I was released from the DCOM error log!!!