Why can't I add names fr Add Bk to EMs after installing T. Bird?

I installed Thunder Bird email along with Windows 8. I was able to import my old address book, but only about 1/3 of the names contained in the old book show up on the scroll bar now when I access the Address Book. I also can't click on a name and have it show up in the address bar of emails; I have to go into the Address Book, copy individual addresses and paste them into the address bar of new emails. Suggestions?