Is it possible to run an external exe (under windows) using native messaging from a HTML application (Javascript) ?
Note:
I have a npapi plugin that runs an exe installed in the client machine. now npapi is deprecated, so I need another way to run my external exe from my website.
You are asking if there is a way for an html page to launch an executable on the client's machine? No, that is not possible. It'd be a huge security hole if it were.
What are you trying to accomplish?