Copy credited to Mike M:-

"Explorer's Folder View:
This particular problem is often the result of a damaged IE (usually IE6)
install or update, often as a result of doing so with Norton or McAfee
running at the time.  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 IE. Do this using Control Panel |
Add/Remove Programs and highlight Microsoft Internet Explorer, 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.
--
Mike Maltby MS-MVP
mcmaltby@hotmail"

Mart