left clicking no longer opens folder

[songdongnigh]

Hello, 

Specs first:
Windows XP home, SP2, all updates & patches except internet explorer 7.
Computer: HP Pavilion 750n, Pentium 4 cpu; 1.6GHz, 1.5 GB ram.
AVG 7.5 Anti-virus/firewall V7.5.478, updated several times per day, run every other day.
Counterspy 2.5.10322 version 599, updated several times per day, run every other day.
Ad-Aware  Personal, up dated & run 2-4 times per week
Spybot search & destroy freeware, updated & run 2-4 times per week.
Firefox 2.0.0.4
Thunderbird 2.0.0.4
VLC media player, windows media player turned off.

Problem:
Recently during a windows search for a file, I got a "windows is having a problem and has to shut down" message, a not unusual occurrence.  However this time after the shutdown, when I left click a file folder, the search screen appears with the name of the file in the "look in" window. I can open the file by then hitting "search", OR by right clicking the folder & hitting "open".  This is of course a bit of a hassle after so many years of left clicking to open a folder.  Plus it means something is screwed up in Windows. 

UPDATE 080307:  I see folks are looking at this but no theories yet. To add interest, the left click problem does not happen with all folders.  For instance I can still left click "mycomputer" OK but then have to right click & open "C" drive etc.  Also, desktop short cuts as for AVG & such left click OK.  The "windows has a problem and needs to shut down" has happend occasioinally since I've had the system, 5 years.   

Any help greatly appreciated.

[songdongnigh]

Hello all, I got a resolution to the left click problem at annoyances.org.  Thanks to all who looked at my problem and pondered for an answer.  Windows is like a crazy house with shifting floors, smoke and mirrors.  I do however enjoy browsing the forum just to see the problems and solutions posted here.  In the spirit of sharing info here is the solution:
My reply to Rich:
Rich, regsvr32 /i shell32.dll did the trick.  Thanks much for your help.  I'll keep the fix handy.  I looked over the knowledge base at Microsoft but could not ask the right question I guess. 
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Rich's solution:
On Tuesday, August 14, 2007 at 5:47 pm, Rich Kurtz wrote:
>You need to restore the default open behavior, try the following:
><p>Go to Start then Run, type regsvr32 /i shell32.dll and press Enter or click
>OK
><p>See if that fixes the problem. If not do the following:
><ol compact>
><li>Start Registry Editor (Start then Run, type regedit and press Enter of
>click OK)
><li>Locate and then click the Default value under the following keys in the registry
>if this problem occurs with folders:
>
HKEY_CLASSES_ROOT\Directory\shell
>
If this problem occurs with drives:
>
HKEY_CLASSES_ROOT\Drive\shell
><li>Click Modify on the Edit menu.
><li>Type none in the Value data box, and then click OK.
><li>Quit Registry Editor.
></ol>
><p>Above taken from: http://support.microsoft.com/?kbid=321186