I have a brand new computer with a brand new installation of Office on it.
I am having the same problem.
After opening and making changes to a file I can close it by pressing the X
in the upper right corner and it will NOT prompt me to save the file.
If anyone knows the solution I'd love to hear it.

"Not Liking MS Office Right Now" wrote:

Some of us may be blond, but there is no blonde-moment going on here. The
same things is happening to one of my clients. She was upgraded from Office
2K Pro to Office 2003 Pro about 2 weeks ago, and this issue just started
happening. If I come across the answer, I will let everyone know.

"brrrrr" wrote:

I have 2 machines that are doing this as well not a blonde moment. If I enter
something into a workbook then go to another program then come back and close
the workbook it does not prompt to save and it has not saved automatically.

"Sammi" wrote:

We are using office 2000, generally when you click on the x in the top right
screen to close the workbook after making changes, you get Prompted to save
changes.

For a client of mine this is not happening.

I have searched the standard options and cannot find where to set this to
give that prompt.

Can someone please assist, or am i having a blonde moment ?