How do I change the default email program in Excel 2007? Options

I recently installed Office 2007 on top of an existing installation of Open
Office.  I've switched over email to Outlook and disabled Thunderbird, but
when I try a "Send" operation in Excel, it brings up Thunderbird, not
Outlook.  I've searched help and tried to google this, but have found nothing.

Don't tell me it is a internet option problem, I got an answer like this:

This is usually an internet options choice.

Open MSI
Tools|Internet Options|programs
change the Email program to what you want.

Won't work! 

Anybody can help. Please Please Please.  I read Chinese, only I can not imput at work.