Sudoku All-But-One

Here's a very easy puzzle, once you know about the "all-but-one" exclusion strategy. Upon examination, it seems almost impossible to find any number, until you search for an all-but-one cell.

What I mean by that is simply this: ALL numbers are blocked in that cell EXCEPT ONE NUMBER. In this puzzle, such a cell exists at F8. Look at the numbers in row-F and column-8, and the "6" in the box containing cell F8. You'll discover EVERY number EXCEPT 7 blocks F8. Therefore, F8 = 7. Now with the 2 in I7, and the 7 you just found, another "all-but-one" occurs at F7, which yields F7 = 5.

Row-F is now missing only 2,3,6, and 2,6 are blocked at F1, so F1 = 3. The 7's in B6,D1,F8,G4 yield E5 = 7. The rest is fairly easy. So the moral of this page is "Look out for All-But-One cases".

Here's the puzzle: