This evening I find that Thunderbird will not 'reply' or 'reply to all' or carry out a spell check - requesting any of these results in 'Thunderbird not responding' and close ' details sent to microsoft'. It will allow 'forwarding' but the window appearing when 'send' is selected does not have a 'send' button although pressing 'close' appears to send the email. It appears that there was a Windows 10 update around tea-time. All had been working normally this afternoon. Any ideas for a solution?