For row 9, number 6 is only possible in cell (7,9)

For row 3, number 6 is only possible in cell (8,3)

For row 7, number 6 is only possible in cell (3,7)

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

For row 8, number 1 is only possible in cell (4,8)

Number 5 is the only value possible in cell (4,6).

For row 6, number 1 is only possible in cell (5,6)

For row 7, number 1 is only possible in cell (2,7)

For box 8, Number 4 is only possible in cell (5,7)

For row 7, number 2 is only possible in cell (9,7)

For box 4, candidates for 2 are all in column 2, so you can remove candidates from other blocks.

For box 4, candidates for 4 are all in column 2, so you can remove candidates from other blocks.

Candidates for 4 in boxes 1 and 2 force the candidates in box 3 to be in the remaining line.

Hidden Pair for 3 and 4, can remove other candidates from these cells.

Hidden Pair for 5 and 9, can remove other candidates from these cells.

X-Wing in columns for 5.

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

For row 7, number 3 is only possible in cell (6,7)

For row 7, number 5 is only possible in cell (8,7)

Number 9 is the only value possible in cell (8,5).

For column 1, Number 9 is only possible in cell (1,7)

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

For column 3, Number 9 is only possible in cell (3,6)

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

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

Number 3 is the only value possible in cell (8,6).

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

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

Number 2 is the only value possible in cell (5,1).

Number 7 is the only value possible in cell (3,1).

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

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

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

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

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

Number 5 is the only value possible in cell (2,3).

Number 8 is the only value possible in cell (3,2).

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

Number 3 is the only value possible in cell (1,2).

Number 9 is the only value possible in cell (7,2).

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

Number 4 is the only value possible in cell (1,3).

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

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

Number 9 is the only value possible in cell (5,3).

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

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

Number 3 is the only value possible in cell (5,4).

Number 9 is the only value possible in cell (6,4).

Number 7 is the only value possible in cell (1,5).

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

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

Number 5 is the only value possible in cell (3,8).

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

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

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

Number 8 is the only value possible in cell (1,9).

Number 7 is the only value possible in cell (2,9).

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