I used a program that transfers apps from an old computer to a new one. I opened Thunderbird on the new computer and all of my account info and folders appear there; however, it won't show me messages. I can get a list of messages to show if I open the inbox in a new window. I can read them but they take up the bottom of the screen, all the way across, blocking the left menu. And I can't delete a message. I can't more on to the next message either. When I first saw this problem, I looked for a solution in Thunderbird menus but nothing works. I downloaded the latest version and reinstalled Thunderbird after uninstalling the older one. The same problem appears. I'm using Windows 10 and didn't have any problem on my old laptop. When I close Thunderbird and try to reopen it, nothing happens.