I am actually having the same problem and it seems to me it occurred after a
windows update. I've tried just about everything including deleting and
reinstalling updates, repairing office 2007, and troubleshooting the plug-ins
thinking one of them may have caused the problem. I was going to attempt to
do a system restore, which I read somewhere solved this issue with another
user, but I came across another problem: Windows Vista Service Pack 1 was
installed a few days prior and because of the size of the udpate, I only have
one other system restore point, none of which are before Excel began to give
me problems. At this point, i'm considering reinstalling Office 2007
alltogether.

Also, if you create a chart within the worksheet, it displays correctly; the
problem arises when you try to create or move a chart into it's own tab.

"Bernard Liengme" wrote:

I have been unable to reproduce this. I did what you did but my 'day' was
about 1 1/2mins. The chart survived. PLEASE let us know if this happens
again. What type of chart; how many data-points; is 'update' adding more
points or changing existings ones?
best wishes
--
www.stfx.ca/people/bliengme


"Stuart C." wrote:

In excel 2007 I have data on a sheet from which I created a chart. I then
moved the chart to its own sheet. I updated the data once a day for a couple
days and the chart was also updated. Then one day I open the file and the
chart is gone. The sheet it was on is still there. The data sheet is still
there, but the sheet is gone (or not visible?) and I can't figure out why or
how to get it back.

This is happened twice now and is getting quite irritating. Any thoughts?