2. Press ctrl+F9 in the signature editing box, and the editing area will appear. Enter: date \@ "YYYY-MM-DD "with braces, that is, the last input is: {date \@ "YYYY-MM-DD"}. If the format has changed, please check the format change help in vba.
3. Insert the time in the signature, and continue to press ctrl+F9 to insert the last paragraph, such as: {time \@ "H:m:ss"}
4. Save the signature and insert it into a new message.
5. If the saved signature is used in the new email and there is no date and time, you can select all (ctrl+a) in the new email and press F9 to execute the VBA macro.
6. If you don't have this date every time you create a new email, you can start outlook automatically when your computer starts, so you can try to create a new email again. If so, you don't have to press F9 to select all.