In Excel, you are supposed to be able to change the rows to columns and the columns to rows (in effect, rotating the sheet through a diagonal axis), by selecting the area to be transposed, and doing a Copy, Paste Special. But the dialog that opens has the Transpose checkbox greyed out.
I've tried several methods, such as selecting a square area, selecting the upper left-hand cell before the paste, selecting the lower right hand cell before the paste, but they all have the same result.
How do I ungrey the box so I can check it?