I use Thunderbird to download (pop3) from various addresses on my btinternet account to sepat=rate mailboxes within Thunderbird. Randomly it downloads mulltiple copies of the same email. Always one with an attachment. They all download showing the same delivery time, and unless I go into my BT webmail page and delete the email form my BT inbox, Thunderbird continues to do it. I've just been away for three days and found 158 copies of the same email downloaded into my Thunderbird inbox. While it's downloading multiple copies, like a stuck gramophone record, it fails to download all of the subsequent emails queuing up in my BT mailbox. I don't know whether the problem is in Thunderbird or my BT mailbox. I have four different BT email addresses and it mostly happens on one specific one, but it has happened a couple of times on one of my other BT addresses. It doesn't happen on every email with attachments, but often enough to be annoying - maybe three or four times a week. In the interests of full disclosure i also download from my gmail account to a separate mailbox on Thunderbird, and have never had this problem happen with gmail (though there's far fewer emails coming through on that). Thank you for any insights.