re : ''I tried to get '''my thunderbird emails''' to forward to my gmail inbox'' Lets start at the beginning. What do you mean by 'my thunderbird emails' ? How many mail accounts do you have in Thunderbird? If at least two. One for gmail and one for another email address. If you have already downloaded emails to the 'other email address mail account' in Thunderbird, why would you set up a Filter to forward those incoming emails to the gmail account, just to download again - this is illogical, so I feel I've missunderstood something. Maybe, do you mean, you accessed your webmail account via a browser for the other email address and set up forwarding to the gmail email address ? Then you created only the one gmail mail account in Thunderbird to see all incoming mail. It would be helpful if you could explain exactly what you have set up. Have you accessed gmail webmail account and set up to receive emails from another server? Having various email addresses forward to eg; gmail is really useful if you use the gmail webmail interface via a browser and like to see everything collectively in one place. Thunderbird is just an email client; a means of having several email addresses (mail accounts) accessing and downloading emails from various servers, so all emails are collectively displayed in the one view. So, if you use Thunderbird then its not necessary to do webmail forwarding setups because you can have as many mail accounts for different email addresses as you like without all the hassle of setting up webmail server to forward stuff. Your query seems to wonder why someone who sends you emails gets a Mailor Daemon response from a server when you have actually received the email either to the original email address or in gmail. This in itself, is not a Thunderbird issue. So, in order to progress can you start at the beginning. Explain what has been set up via webmail for both the 'other email address' and 'gmail'. Have you really have set up a filter to download everything to a mail account for the 'other email address' and then forward to another gmail address just to download again?