I have an email account on Thunderbird (jetmayor@gmail.com). I can get to this account on one laptop but not on my other newer laptop. The screen asks me to sign in and shows my email address as above. Underneath the shown email address it says 'Forgot email?' Underneath this it says: Before using this app, you can review Mozilla Thunderbird Email’s privacy policy and terms of service. Create Account NEXT Whatever I press it goes to another screen and says: 400. That’s an error. The server cannot process the request because it is malformed. It should not be retried. That’s all we know. The email address did work OK for months and I just don't know how to get it back. I've tried to delete the account and then reinstall it but that hasn't worked. My other email addresses are still working fine. I can still access the faulty address directly on Google Mail so I know it still should work. It's possible I have changed the password in the google account. I have tried this password in Thunderbird but to no effect. Is there a way to reinstall the faulty address? Help! Any help would be greatly appreciated.