Paste Special -> Transpose not working

I did a search in here but didn't find an answer so here goes nothing...

I have a spreadsheet with data from A1 to H1 down to A275 to H275. I select all of it, Copy, go into the Sheet2 tab and select A1, Paste Special -> Transpose and it give me the following error message:

The information cannot be pasted because the Copy area and the paste area are not the same size and shape. Try one of the following:
- Click a single cell, and then paste.
- Select a rectangle that's the same size and shape, and then paste.

Click to expand...

For the life of me, I can't figure out why it's not working! I have done this many times with other spreadsheets. Has anyone ever experienced this? If so, were you able to resolve it and how?

Many Thanks,
Mike