@skeezix

I would recommend you to use the INDEX formula used in Sheet1!A17:M31 instead of that in Sheet2 (TRANSPOSE).

If you absolutely should want to use the formula in Sheet2 be aware of the following.

You must count the size of the original range - here 13*26 (13 rows and 26 columns).
Then you must select an empty range which is 26*13 (26 rows and 13 columns)
With such a range selected you must enter the array formula:

=TRANSPOSE(A2:Z14)

but instead of just pressing Enter you must hold down Ctrl and Shíft before pressing Enter. If you do it correctly Excel will automatically put braces {} around the formula.