Reported <Next File in Directory> does not work in non-Latin named directories.

[gegogi]

I'm using Korean Windows 7 and I have some photo directories with Korean names.
Only for those directories, some file navigation functions does not work as expected.
They include <First File in Directory>, <Next File in Directory>, etc.
This buggy behavior is always reproduced in the latest version 4.33 of IrfanView.