It means that you can't sort cells that are merged !!

There are many other problems that merged cells can cause, and many of
the contributors to these groups will advise you to avoid them like
the plague (including me).

Pete

On Jan 30, 11:19*pm, Siliconbytes
wrote:
I have a worksheet in which some of the columns are a single cell wide, and
others are merged cells consisting of two or three columns wide. When I try
to sort the rows in ascending order alphabetically based upon a column that
consists of two merged cells, I get the message "this operation requires the
merged cells to be identically sized." What does this mean?

Thanks in Advance