Recently upgraded to Office 2010 from Office 2003 running on Windows XP.
In Excel 2010 whenever I click outside the cell being edited the "undo" button grays-out and I loose all ability to undo any previous changes. As long as I don't click outside the cell being edited the undo button is active and will undo any changes...as long as I don't click on another cell. The second I click on another cell the undo button goes gray and I loose all ability to undo my changes. I have also tried CTRL+Z to undo and that too is inactive once I click on a new cell. I had this identical problem with Excel 2003 and was hoping that the upgrade to 2010 whould fix the issue, but apparently it simply carried over to the 2010 version. I have uninstalled and the reinstalled Office 2010 with no change. I have checked Access 2010, Word 2010, Outlook 2010 and PowerPoint 2010 and the problem does not occur on those Office 2010 products.
I have looked through all the settings and options in Excel and wasn't able to find any setting that may affect this. I have also searched for solutions online with little success.
Any help, tips or ideas on how to fix this would be greatly appreciated.