Understand that Notepad++ will open any file, even if it’s a binary file (executable is one type of binary file). That’s not to say that Notepad++ is the most appropriate application to view every file with.

Understanding what a file is using the file extension is just a first step. You should also try to figure out where the file came from as that can have a bearing on the content. As I said before the extension can often give you some information (Google search), but isn’t a 100% reliable means to identify the file type.

Terry

Any help is much appreciated

Generally with an unknown filetype, Google it. From google’s response, I went to a relevant website here.

So it’s possibly a subtitle file for a video/film, so plain text. So if you opened it in Notepad++ and it doesn’t look like plain text, then likely it’s another type of VTT file. No-one owns file extensions, anyone can use any type. Developers will tend to use one relevant to what they output though.

Terry