"Sudoku in error" is made and published by Helena & Johan Jager more than a decade ago.

But I did not find this puzzle on this forum and he is really nice.

....98.2....2.7841.874.1...85..2..19.218.253.76..5..86...9.431.1923.5....7.68....

This Sudoku is designed wrong and is full of mistakes.

You can see in column 8 there are two 1's.

One 1 must be in error but you do not (yet) know which is in error.

Additional rules:

1. Per row, column and box there is exactly one mistake.

2. Each mistake conflicts 3 times: in a row, in a column and in a box.

3. Each mistake conflicts with other cells that are all correct.

4. Within a box a mistake will never conflict with another number on the same row or column

5. Digits 1 to 9 are all in error exactly once.

6. Digits 1 to 9 are present nine times each.

The challenge: solve the Sudoku in error.

Errors should not be corrected ! (You have to make extra errors yourself)

There is only 1 solution.

More tips: