Windows Explorer left pane additional icons

Hi All,

I am facing the exact problems as described in
http://www.mcse.ms/message715102.html.
On the left pane, sometimes I get many icons (used to display the files
with unknown extensions). There is no problem with the virus or
spyware. I checked for all these.
Please help me for this unusual issue.

Thnaks in Advance.
Anubhav

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