Thanks for the help. I think that and the github .exe are the same version, as the byte count is identical. Anyway, I found the problem - the advice to not include blank lines at the end means don't append a return to the final "End" either. I should have caught that earlier, must have been half asleep.ad windows version: Have you tried downloading the zip (containing an exe) from qqref's original post. This version works fine on my laptop (Win 7).

Also the 3x3x3.def file on both github and qqwref's site isn't Windows-friendly and needs CRs added before it will work.

Yeah I should have read the whole thread, and the (excellent) readme.txt in more detail However, I still can't get it working. When the pieces are replaced with '?' it fails to find any solution, even U R U' R'. If I include hints then it does find some solutions, but not all of them - only those that also leave solved pieces at URF/UR where the F2L pair started. See below for scramble file and output.ad F2L-Solver: In the scramble you have to ignore the last layer pieces with a ?. E.G. if your scramble is 1 3 7 9 2 6 ... and you want to ignore the last layer, write ? ? 7 9 ? 6 ... In the definition file you're only specifying the pieces, which may be ignored. To really ignore them, write ?s.

Scramble file:-

And the output:-

Code:

```
Scramble Piece configuration as reported by ScrambleAlg R U R' U'
CORNERS
5 2 4 3 1 6 7 8
2 0 0 2 2 0 0 0
EDGES
1 2 4 5 3 6 7 8 9 10 11 12
0 0 0 1 1 0 0 0 0 0 0 0
End
Scramble U layer pieces replaced with ?
CORNERS
5 ? ? ? ? 6 7 8
2 ? ? ? ? 0 0 0
EDGES
? ? ? 5 ? 6 7 8 9 10 11 12
? ? ? 1 ? 0 0 0 0 0 0 0
End
Scramble U layer pieces with ? prepended
CORNERS
5 ?2 ?4 ?3 ?1 6 7 8
2 ?0 ?0 ?2 ?2 0 0 0
EDGES
?1 ?2 ?4 5 ?3 6 7 8 9 10 11 12
?0 ?0 ?0 1 ?1 0 0 0 0 0 0 0
End
```

Code:

```
Solving "Piece configuration as reported by ScrambleAlg R U R' U'"
Depth 0
Depth 1
Depth 2
Depth 3
Depth 4
U R U' R'
Depth 5
Depth 6
Depth 7
Depth 8
U F' U2 L' U' L F U2
R2 B' D' R D R2 B R'
Max depth reached, aborting.
Solving "U layer pieces replaced with ?"
Depth 0
Depth 1
Depth 2
Depth 3
Depth 4
Depth 5
Depth 6
Depth 7
Depth 8
Max depth reached, aborting.
Solving "U layer pieces with ? prepended"
Depth 0
Depth 1
Depth 2
Depth 3
Depth 4
U R U' R'
Depth 5
Depth 6
L' U R U' L R'
Depth 7
U F' L' U' L F U
Depth 8
U F' U L' U2 L U F
U F' U2 F R U' R' U'
U F' U2 L' U' L F U2
U B' R U' R2 U R B
U B' R U' R' U B U'
R2 B' D' R D R2 B R'
Max depth reached, aborting.
```