jonib, thank you! it helps me with same problem...
my log is:
12:15:40 I have crashed in function 'DefragThread' in source '.\MyDefrag.cpp' on line 52.
Exception: ACCESS_VIOLATION (the memory could not be read or written)
Command line: "C:\Program Files\MyDefrag v4.3.1\MyDefrag.exe"
Context is not locked.
1. At line 121 in 'd:\www.mydefrag.com\sources\lib\programhints.cpp'
2. At line 142 in 'd:\www.mydefrag.com\sources\lib\programhints.cpp'
3. At line 310 in 'd:\www.mydefrag.com\sources\lib\programhints.cpp'
4. At line 2485 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
5. At line 43 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
6. At line 1267 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
7. At line 43 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
8. At line 4766 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
9. At line 43 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
10. At line 4766 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
11. At line 43 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
12. At line 4766 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
13. At line 43 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
14. At line 4766 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
15. At line 43 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
16. At line 4766 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
17. At line 43 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
18. At line 4766 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
19. At line 43 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
20. At line 4766 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
21. At line 43 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
22. At line 360 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
23. At line 43 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
24. At line 4766 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
25. At line 43 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
26. At line 4766 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
27. At line 43 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
28. At line 4766 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
29. At line 43 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
30. At line 4766 in 'd:\www.mydefrag.com\sources\lib\interpret.cpp'
31. At line 590 in 'd:\www.mydefrag.com\sources\lib\execute.cpp'
32. At line 709 in 'd:\www.mydefrag.com\sources\lib\execute.cpp'
33. At line 916 in 'd:\www.mydefrag.com\sources\lib\execute.cpp'
34. At line 47 in 'd:\www.mydefrag.com\sources\mydefrag\mydefrag.cpp'
Trying to crash the other threads for debugging purposes...
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