Date 01.01.1970 after deleting a message

[ps1304]

sometimes when I delete a message in Thunderbird, inbox or local folder; the message wont disappear and Thunderbird displaying an empty message with date: 01.01.1970

[Ariadne]

I get this too in my Unified Folder inbox with some messages from my Yahoo account.  If I go into the Yahoo account in the All Folders area I can get rid of the message.  It is a bit irritating but manageable.