hi malindaemail365, let me start try help you, sounds like a server setting, either on your server (aka the service provider) or in your client (aka Thunderbird), to start with * need more info, is this an IMAP or POP email account? and are you using any of the "big" email providers eg. Outlook/Google etc. ? or is this an account with another provider? * also, could you pls check in Account Settings in "Synchronization & Storage", do you have marked "Keep messages in all folders for this account on this computer" on or off ? * IF an IMAP account (but not if a POP account) you could try delete and re-create, then do not change any settings, use the standard settings provided by Thunderbird, START TECHNICAL NOTE An IMAP account keeps emails on the server and the email client (aka Thunderbird) normally downloads emails to your local computer, but you can actually choose to download all or none or only specific folder(s) A POP account on the other hand does normally download all emails to your local computer and delete emails on the server, caution is required since you then do only have a copy of your emails on your local computer. If you are unsure which server type, open Account Settings, under "server settings", see "server type" (where stated either "IMAP Server Type" or "POP Server Type") END TECHNICAL NOTE All the best from Stockholm