Poderosa’s preference files are located in the following directory:
(1) Normal Edition
C:\User\[User Name]\AppData\Roaming\Poderosa\poderosa.json
(Depending on Windows’s environment, this pass is not used, or it is hidden attributes so it can’t be seen from Explorer.)
(2) Portable Edition
Same directory as execution file, Poderosa.exe.
Also, there is backup of setting file that could be finally read in normally in poderosa_backup.json file.
If you think operation is wrong in setting file, please try deleting these files and start in initial state.