Automatic shutdown upon grouping tab

[muerindah]

In a workbook, in Excel 2010 I have a worksheet linked to other sheets with pivot tables of information. Each row contains various informtion from period to period by location. This infromation is then group in rows by states. I also have grouping on the columns for a monthly activity.

Upon selecting the expaning grouping button usually happens with the ungroup all Excel automatically closes the workbook. I can't find any errors that I am aware.

Thank you
Minda