I assume you have tried toggling the setting in Firefox between Outlook and, say, Gmail:

orange Firefox button or classic Tools menu > Options > Applications

In the search box, type or paste mailto and pause for the list to filter.

Change the setting and OK to save it, then return to the dialog, change back, and OK again.

You also might want to toggle the setting at the OS level between Microsoft Outlook and the native Windows Mail client in a similar fashion. In Windows XP you could use IE's Options dialog, Programs tab, for this, but I'm not sure in Windows 7.

Since one possibility is a problem in your Firefox settings (including the possibility of interfering add-ons), and another is a problem at the Windows level (e.g., Registry settings), it would be useful to try to identify which one it is. One quick way to distinguish is to create a new Firefox profile. It will start up with all factory settings. You can switch back to your existing profile after testing.

First, I recommend backing up your Firefox settings in case something goes wrong. See Backing up your information. (You can copy your entire Firefox profile folder somewhere outside of the Mozilla folder.)

After closing Firefox, start up again in the Profile Manager as described in this article: Managing profiles.

With the new profile, can Firefox successfully create a message in Outlook?

Nothing I try works. I click on an email link and nothing at all happens - no errors, nothing.

Hi andiellen, this is a hot-linked email address on a web page -- and it affects all sites you've tested, or just some sites?

What have you tried so far, and what email program or site do you want to be fired up when you click the link?

Try to delete the mimeTypes.rdf file in the Firefox Profile Folder to reset all file actions.

• http://kb.mozillazine.org/mimeTypes.rdf
• http://kb.mozillazine.org/File_types_and_download_actions#Resetting_download_actions

You can use this button to go to the Firefox profile folder:

• Help > Troubleshooting Information > Profile Directory: Open Containing Folder

I backed up my profile and did a reset and that did it. Guess I'll start adding stuff back one by one and see what broke it.  :-(