- Implementing an nsICommandLineHandler on Windows may trigger a bug that causes an error message ("Windows cannot find the file specified") to be displayed when opening external links (like from a shortcut or from an external application). Deleting the "(Default)" values in the following registry keys will fix this:
You can also do this from within your XPCOM component using Windows registry interface.
Some more links on the matter:
- A Mozillazine post.
- A blog post.