Read this courtesy of MikeM.
Joan

This particular problem is often the result of a damaged IE6 install, yes
I
do realise you are talking about Windows Explorer rather than Internet
Explorer but the two are linked.  May I suggest that you try repairing
IE6.
Do this using Control Panel | Add/Remove Programs and highlight Microsoft
Internet Explorer 6, click Add/Remove and then on the next screen select
"Repair Internet Explorer" and then OK.

If you don't have an entry for Microsoft Internet Explorer but rather it
reads
something like Internet Explorer Q?????? don't worry.  This is because you
have installed a cumulative update for Internet Explorer.  You will need
to
uninstall the update, then go back into Add/Remove Programs, look again
for
Microsoft Internet Explorer, repair it and then reinstall the latest
cumulative update.

If this doesn't work or you have no entry for Internet Explorer in
Add/Remove
Programs please post back and someone will hopefully post further details
on
how to repair Explorer.
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