The bad thing is though,even though I have the usual tabs at the top , the page only lists the subject titles & the number of the order they were received in. The usual columns like who  the sender is  , & date & time received aren't there.  
Do you know how I can make it go back to normal, where I have the usual columns?

This morning when I opened Mozilla Thunderbird, I wanted to see the important emails that I had previously "Starred", but the usual Starred tab at the top of the page wasn't there. So without making note of every step I took & now can't remember, I finally got my email page to have the "Starred" tab. The bad thing is though,even though I have the usual tabs at the top , the page only lists the subject titles & the number of the order they were received in. The usual columns like who the sender is , & date & time received aren't there. Do you know how I can make it go back to normal, where I have the usual columns? Thanks