Why do I get this alert message across the bottom of my screen when I double-click to open an email in my INbox? It is in a yellow box across the bottom of a pre-populated draft 'return to the sender" email. ''A unique identity matching the From address was not found. The message will be sent using the current From field and setting from identity Robert Hill <arnilmmproductions@gmail.com>" It doesn't mark the original email as 'Read' when I close it. But if I right click on it, it gives me the option of opening it a new Tab, a new Window, or a Conversation. The problem seems to recur after a Thunderbird upgrade. Hoping to get your response and a solution soon. Thank you.