See http://support.microsoft.com/kb/918165 "Problems in Windows
Explorer or the Windows shell after you install security update
MS06-015".

Michael Laferriere wrote:

I have four machines in the same office. All are running Word 2002 with SP3
and are current in both Windows & Office updates. Two have developed a
problem recently when you go in to Word, click on File, Click on Open and try
to click on a file or folder to open it, the window hangs. Everything else
seems to run ok. All machines are current with Norton Antivirus and I have
tried running several spam tools including Windows defender with no results.
Two machines are affected and two arent. If you use Windows and browse to any
folder or word file and open the file that way things work perfectly. Also,
about the same time on both affected machines Internet Explorer has developed
another odd quirk. When you type an address into the address bar it sit's and
does nothing but isnt locked up. If you add the http:// before the address it
works perfectly. The people in this office are not prone to playing with
settings or heavy surfing of troublesome sites. Any idea's?