Please expand on your issue. No idea what you want to create a mailing list in ????? If this is a Thunderbird Issue you should be posting here : https://support.mozilla.org/en-US/products/thunderbird as well as checking their help. Is this what you are looking for ???? https://support.mozilla.org/en-US/kb/how-create-and-use-mailing-lists-thunderbird Please let us know if this solved your issue or if need further assistance.