With the new packet logging interface disabled, the hotkey Ctrl+I and the button to view the log do not open the file anymore.
File exists?
Yes, it does.
Let me see option "LogPath" and "LogViewer" in ini file.
I found the issue to be the relative path I set for LogViewer, totally forgot that, because it used to work without any issues.
I had set LogViewer to .\csvfileview.exe. Now I set it to just csvfileview.exe it seems to be working again (the executable is inside Simplewall's folder).