Has anyone else experienced this problem? Is there a known solution?

I have Office 2003 SP2 and Win XP Pro SP2 on an HP T5600 Centrino Duo laptop.
On several occasions, I have opened Excel, edited a worksheet, copied a
portion of the work to paste into Word, but when I then open Word, Excel
closes without warning and does not attempt to recover the document when I
reopen Excel.

On multiple (but not necessarily all) occasions, the Excel document was a
pre-existing document that included macros, and was the only Excel document
that had been open at any time in that session.

Jerry