I am SO excited!! I just figured it out!! PHEW!!! Persistence pays off. SO I will share with you NOW.
Go to Start Menu, Press DEFAULT PROGRAMS. Click "Set your default programs" Click on Thunderbird in left column; Thunderbird info will appear in box to right....below that choose "Set this program as default" and then press OK....then you get to test it out right away!! Let me know if it works for you. I am SO STOKED
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