The response to that 2006 post points at a Frozen panes problem. But since the
OP didn't reply, who knows what solved it.

Zandweter wrote:

See also this more recent post
http://www.microsoft.com/office/comm...=en-us&m=1&p=1

"Zandweter" wrote:

True, ik looks like a training issue. However the problem seems to occur all
by it self (they say ;) . Maybe just replace user and reboot :)

--

Dave Peterson