I've used Thunderbird for years and have all my emails on my laptop. I now want to move them to gmail so I've set up my gmail as an imap account in thunderbird which all works fine. However, when I copy emails from my local folders to the IMAP account it never works properly. It quite often fails to copy all emails which then causes a huge problem as I have to manually check which emails in which folders it's failed to copy and it's quicker to start again. I've tried dragging the folder from local folders to the imap account and even used Copy Folder extension but almost everytime it fails to copy all emails in the folders. Has anyone managed to successfully move emails from thunderbird to gmail imap account? All I've found online is that you should be able to copy which I can but it simply does not copy all emails in a folders. I have thousands of emails to copy and don't want to have to do it manually and manually check each folder as this would be too much.