Number 5 is the only value possible in cell (5,1).

Number 9 is the only value possible in cell (7,7).

Number 2 is the only value possible in cell (1,7).

Number 3 is the only value possible in cell (7,9).

Candidates for 2 in boxes 2 and 8 force the candidates in box 5 to be in the remaining line.

For row 5, number 2 is only possible in cell (9,5)

For row 3, number 2 is only possible in cell (4,3)

For box 2, Number 9 is only possible in cell (6,1)

For row 1, number 8 is only possible in cell (1,1)

For row 2, number 2 is only possible in cell (7,2)

For row 8, number 2 is only possible in cell (6,8)

For column 6, Number 5 is only possible in cell (6,4)

For box 6, candidates for 8 are all in row 6, so you can remove candidates from other blocks.

For box 3, candidates for 6 are all in column 8, so you can remove candidates from other blocks.

Candidates for 3 in boxes 1 and 7 force the candidates in box 4 to be in the remaining line.

Naked Pair for 6 and 7, can remove these as candidates from other cells.

Naked Pair for 1 and 6, can remove these as candidates from other cells.

Number 5 is the only value possible in cell (2,2).

For row 2, number 1 is only possible in cell (3,2)

For row 3, number 5 is only possible in cell (9,3)

Number 1 is the only value possible in cell (9,9).

Number 4 is the only value possible in cell (8,7).

Number 1 is the only value possible in cell (6,7).

Number 4 is the only value possible in cell (5,9).

Number 9 is the only value possible in cell (2,9).

Number 3 is the only value possible in cell (2,3).

Number 9 is the only value possible in cell (3,3).

Number 2 is the only value possible in cell (3,4).

Number 1 is the only value possible in cell (5,4).

Number 3 is the only value possible in cell (8,4).

Number 9 is the only value possible in cell (1,4).

Number 2 is the only value possible in cell (5,6).

Number 4 is the only value possible in cell (2,8).

Number 3 is the only value possible in cell (3,8).

Number 6 is the only value possible in cell (1,9).

Number 7 is the only value possible in cell (1,2).

Number 6 is the only value possible in cell (3,1).

Number 7 is the only value possible in cell (8,1).

Number 3 is the only value possible in cell (9,1).

Number 6 is the only value possible in cell (8,2).

Number 3 is the only value possible in cell (1,5).

Number 8 is the only value possible in cell (6,5).

Number 4 is the only value possible in cell (6,2).

Number 8 is the only value possible in cell (4,2).

Number 1 is the only value possible in cell (8,5).

Number 6 is the only value possible in cell (2,5).

Number 7 is the only value possible in cell (4,5).

Number 6 is the only value possible in cell (4,4).

Number 7 is the only value possible in cell (7,4).

Number 1 is the only value possible in cell (2,6).

Number 7 is the only value possible in cell (3,6).

Number 4 is the only value possible in cell (4,6).

Number 3 is the only value possible in cell (6,6).

Number 8 is the only value possible in cell (9,6).

Number 6 is the only value possible in cell (7,6).

Number 8 is the only value possible in cell (7,8).

Number 5 is the only value possible in cell (8,8).

Number 9 is the only value possible in cell (4,8).

Number 7 is the only value possible in cell (9,8).

Number 5 is the only value possible in cell (4,9).