I am a new user and am trying to set up Thunderbird on a Windows 10 machine with my Gmail and Posteo accounts. I have already done so on my other Windows 7 machine with no problems. On the Windows 10 machine, however, when setting up Thunderbird I cannot get beyond the first screen setting up mail email address. The window simple halts with "Checking password" and a spinning ball forever trying to log in to either account (Posteo or Gmail). I am using the correct passwords, of course. Attempting to do the manual set up , I simply get a message saying "incoming server already exists", and nothing proceeds. All of this is on a fresh install of Thunderbird. I have uninstalled and re-installed and I get the same effects described above. I cannot proceed past this initial account set-up page. Does TB not work with windows 10??