How Do I Fix Inoperable Send Link/Email Features in Firefox?

[gguy]

am unable to use any of the "send link/send email" features in
Firefox .
I have the most recent version of Firefox.
The send link feature works fine in Internet Explorer.
Both Firefox and Thunderbird are the default programs.

I found a possible resolution at an XP help forum through a Google
search for
"Firefox send link problem" and wondered if this is approved approach
to resolving
this problem.
"Firefox send link fails while IE sends links to Outlook Express"
http://forums.techarena.in/showthread.php?t=62412

It reads the mailto settings. Click Start, Run and type REGEDIT.EXE
Navigate to the following branch:

HKEY_CLASSES_ROOT\mailto

Using the Export option in the File menu, export the key to a REG file

Close Regedit.exe

I exported the file but don't know what to do next.

Any help on this matter would be greatly appreciated.
Thanks very much.