You cannot add a comment to the selected blank table cell in Word

In Microsoft Office Word 2003, when you insert a comment into a blank cell in a table, instead of the comment being anchored to the blank cell, the comment may be anchored to text in a cell to the left.

Note This problem does not occur when the cells to the left are blank.

To work around this problem, type a space in the cell where you want your comment to appear.