On our intranet site, we have various MS Office documents linked. When I click on a Word, Excel or PowerPoint file, Firefox gives me the option to Open, Save or Cancel. When I click on Open, the appropriate app is launched and the file is loaded. This is perfect. But for some reason, when I click on a linked Visio file, I only get the option to Save, which is inconvenient.

I know that Firefox knows the linked file is a Visio file because it tells me so in the dialog box: "You have chosen to open example.vsd which is a: Microsoft Visio Drawing".

How can I make Firefox launch Visio when I click on a linked Visio file?

Update: Firefox is not launching Visio when I click on a linked Visio file because the web server does not identify the content-type correctly. It identifies the Visio file as application/octet-stream instead of application/x-visio. (Thanks Grant Wagner.) This explains why it doesn't work. And in my case, I may be able to get the Apache config file changed, but this is not certain.

However, I would love to know if there is a way to configure Firefox itself to launch Visio based on some other criteria, like file name extension. This way I can open Visio files even if I don't have access to the Apache configuration.