Open With ... not working

[gmoises]

The command line gets broken at spaces and the target application can not find the file.
if the filepath does not contain spaces, "Open With ..." functions perfectly

[xnview]

on Windows?

[xnview]

Thanks to your detailed description I can reproduce the problem.

[xnview]

This problem is supposed to be fixed in XnView MP 1.5.1. Please check and confirm the bug fix here.