Hi Gerrard That is the way IMAP is supposed to work. All email is kept on an online server. Each of your devices 'views' the emails but they are not stored on your own device unless you copy the message to 'local folders'. If you delete a message from any of your devices or when using webmail, that email is deleted. When you look at the email 'view' from any device after deleting from anywhere, that message is not there. You can choose to save a message on one device, and then delete it from the online server. In that case, you would save it to 'Local folders' in Thunderbird, and then delete from Inbox. Then that message would only be available on one device in 'Local folders'. POP email works quite differently. If you switched recently it may take a little getting used to. Agnes